Species Endangered (MS-Blog Series from) XII / 09

Gastric-brooding Frog

Class: Amphibia

Order: Anura

Latin name: Rheobatrachus silus / R. Vitellinus

Range: (Australia) - Inhabited a limited ranges at eastern Queensland.

IUCN: EX (CR) / EX (CR)¹, CITES: -/- (not checked)

(a 2009 situation)

Sometimes word of the day, frogs are more important than people usually realize. Them are – like echoed also by us in our earlier amphibian post – supposed most threatened from the animal orders, not the least by the climatic change, etc. But, as they also are often mentioned having been first species that moved from seas to the land, one easily presumes them most 'primitive' of the terrestrial animals. In fact that appears false assumption, for we learn that their extant main groups (Frogs, Salamanders, and limbless Caecilians) actually are timed roughly for the same periods as the modern reptiles. Oldest from reptiles still extant genera, turtles and crocodiles therefore appear slightly more distant from evolutionary origins than current amphibians families, it seems. (However, also appears stated that earliest amphibians were around some 300+ Million years in the past, already). In spite of how exciting these preceding view-points might be, our interest in this (brief) text is delimited for the variety of colourful amphibian species. Since the rain forest species are not only most numerous but most impressive from looks (as well most threatened of them, also often said), this consists largely from representing them.

So, the above frog(s) examples for this part, are not selecte from the reason of being extinct – actually they represent only singular species among several mentioned in this text. Nevertheless, and like we find mentioned, the Rheobatrachus (genus of frogs) contained above mentioned two species (R. Silus/.Vitellinus), both rather exceptional. Mentioned as gastric-brooding frogs from the reason that in both the reproduction was by female frog ingesting it's (fertilized) eggs, which then developed for juveniles in the frogs stomach (and were finally vomited as juveniles from it's mouth). Unique manner even among the frogs which show multitudes of variety and peculiar examples at their reproduction. In our only marginal acquaintance from the life of the frogs, this makes us almost to think the truth often being stranger than fiction.

Anyway, sad part of course is that no Gastric-brooding frog seems been found after their rapid disappearance during brief period in begins of 1980s (Been only known for science since about 1972/3). At that time the reasons and causes for frog extinctions in general weren't yet too clearly understood, and so, in lack of any especial knowledge from the species we're not focusing on that here more precisely. However, at the amphibian declines generally, an increased vulnerability of the small frog populations is nowadays often mentioned. Most alarming prospect, equally often noticed, is their habitat fragmentation(/destruction), like mentioned in following paragraphs:

"Shrinking Habitats. Pressure generated by the world's expanding human population creates an insatiable demand for land that results in the destruction of the natural habitat of plants and animals. This process is offset, to a very small degree, by the creation of natural reserves, but these can become prisons rather than havens for animals such as amphibians. Many amphibians live in small, local populations, the longterm survival of which depends on the occasional immigration of animals from other such populations elsewhere. Increasingly, amphibians are being forced to live in fragmented landscapes within roads, built-up land, and agriculture separating one population from another. There is growing evidence that this isolation leads to an inbreeding and a consequent loss of genetic diversity, decreased survival rates and an increased incidence of anatomical deformities.”(Halliday-Adler 2002, p. 32-33)

As well is said: “Although amphibian population declines have attracted a great deal of scientific and media interest, there is no reason to think they are unusual or unique. All the factors that adversely impact upon amphibians pose a threat to other forms of wildlife. [...]"(Halliday-Adler 2002, ibid.) ...Remarks at the book then continue with mentioning the disappearance in freshwater habitats noticeably having impaired the amphibians populations for some time (other wildlife as well). Also, fx how the protected areas should be designed to create optimal conditions in nature reserves is stated being increasingly important, since the populations based on single limited area are more likely to face eventual extinction, sometimes despite protection. As well appears noticed, that for smaller part/some level the diminished habitat can be replaced by habitat creation - like the underpasses and tunnels built in some places to create amphibians some safety from roadkills, fx on routes for their breeding sites (ao efforts at their protection mentioned). (Halliday-Adler, p. 33-35) Remembering that (in cases) populations of thousands individual frogs have been noticed rapidly vanished (as result of increased vulnerability to variety of threat), also gives some importance for the above mentioned.

The amphibian decline in overall presented at our earlier post, we'll leave that for these few words and the following text mostly serves the purpose of presenting examples from variety in the amphibian lifes. But, fx the Amphibia web's pages about the global decline contain some further information, probably (also seems contain the downloadable Amphibian Action Conservation Plan). And for the interested, from various threatened amphibian around world, EDGE's Amphibian top 100 list presents many, any of those less usually or not commonly noticed. (And – further more - not forgetting to mention this word on behalf the amphibians ; we also learns from it about another exciting frog species, the Phantasmal poison frog (EN), whose skin secretions contain some particular compounds, possibly found of use in the human medicinery as well as aid in the research of pain-killer medicines (or something like that, sounds not at all too unsual or surprising, concerning the amphibians have especial skin formations in overall, etc) - Even though I find that least interesting from aspects presented on the text (Maybe so 'cause I don't much care from the medicines markets and labs, and even less from the prospective views of the global medical businesses or firms. Nevertheless, despite my slight antipation, it's sometimes mentioned that penicillin probably has been one of the most benefiting inventions in the preceding century - for human kind.)

...But for to stay on our main topic in this; following paragraphs are focused on colourful and exciting characteristics of the amphibians. Many of the species mentioned in the following, I suppose, are from the better known colourful and sometimes also the most usually represented examples. In spite of that, there's a lot especial and interesting in them to familialirize with (So I noticed when writing this...).

Often in the nature, bright colour serves purposes of aposematism (ie as warning sign to potential predators from species being distasteful/of it's toxic defenses). Some frogs also exhibit polymorphic appearance (different colour patterns found even in the individuals of same species). From this, again the most popular examples are to be found in the small toxic frogs of South American forests (Presented in the pic above), that appear in variety of species (there's at least three separate genera of these tiny frogs with toxic defenses). Variability in the skin colour and pattern also more generally appears typical to amphibians, as well as does the sexual dimorphism; In several cases male and female frogs exhibit rather different looks, fx. Further more, some are mentioned changing their overall skin color according to body temperatures – not quite same manner or as impressively as the chameleons, but some fx change their tones of color according the surrounding environment or frogs mood (like mentioned from the European leaf frog, Hyla arborea (LC) - also, when exposed to sunlight it appears paler by color.)

Colour patterns appear as method to warn their would-be-predators, but it's also found commonly used as camouflage by the frogs - to avoid detection from potential prey. Most frogs are carnivores - about majority eat insects but larger species also various other prey and fx typically the diet of some rain forest frogs ranges from worms and little snakes to even small mammalians (like bats, fx). To hide from their prey, certain species are found having adopted/imitating the usual background colors, even to level their skins reflecting smaller variations of litter and leaves found on the forest ground. Some horned frog species most typically mentioned examples from such adaptations. (Another interesting example, ao, we find presented in the pocket guide from East African frogs [2006]; in form of (Tanzanian) reed frog species (Hyperolius Orkarri), whose overside colours are mentioned closely matching the granite rock environment it lives at – Acc. book species is only known from few areas).

From the use of colour as warning from species palatability, there's also plenty examples at the Salamander (Caudata) families (Perhaps, not so evident of the species in pic above, Golden-striped Salamander, Chioglossa Lusitania, VU) - Salamanders and Newts form a parallel group for Frogs and Toads, the Newts being (in general) more accustomed to watery environments and Salamanders usually more terrestrial, except during their breeding periods. They typically are impressive from appearance and colour; An european species most renown of them, Fire Salamander (Salamandra salamandra, LC) represents very bright yellow colours. It has also interestingly given reasons for many odd beliefs in the past. According to the most usual from these, it was in the Middle Ages widely asserted capable of setting up fires by its sole presence and also (was believed) resistant to flames. According to another often mentioned anecdote, this false belief was already widespread and common during the Antique; Even to the level that Pliny the elder (23-79 A.D.) experimented it's accuracy when preparing his renown book, Naturalis Historia; - by throwing the fire salamander into flames, with expectable result of course. As noticed, that apparently didn't prevent the same false belief to persist through centuries for hundreds years afterwards.(...the underline on this added 28.08.2015) (Serves well also to show how a mistaken belief and fallacy can remain, and in time become part of the shared common consciousnes.)

But, from the real qualities of the Fire Salamander, it's fx mentioned that a lot variation appears between coloration of the individual animals. Some are almost completely yellowish, some represent only small bright dots. Many other salamanders as well represent by bright color a warning from their toxic defences (even though that doesn't completely prevent them being predated) – however, I've not checked if that the case also in genus plethodontidae, salamanders that are mostly renown from breathing only through their skin since they do lack the lungs completely. As for other interesting salamander characteristics, it is mentioned that some species - like the N. American Eastern newt (LC)(Pic below from Eastern Newt in the eft phase, adults are mentioned differing from color) - can find their routes from several kilometers distance for the watery streams and ponds they've been taken far away from. Even more, it's mentioned that they are able to use the position of the sun, with the aid of sensing polarized light to perceiving their position and using that (information) for directioning. As well mentioned, it been demostrated that they are able to detect Earths magnetic field and use that to form some kind of 'maps' from the surrounding environments - having sort of "GPS-system" of their own; ie it is noticed suggesting that the Newts nervous system maybe able to develop and store some detailed information from their living regions. (Halliday-Adler book, on p. 52). (How precisely/how well that mechanism is understood/studied, I've not checked, but there's a few researches from the subject listed at the end of this post). Actually, various animals similarly use some kind of 'compass' to make their routes and journeys, most renown are the migrating birds. Salamanders, whose plentiful families are distributed around the most continents (excluding the Africa and Australia), appear likewise threatened as the other amphibians by varying degree – 3 species are listed critically endangered, at least (Halliday Adler, p. 56-59).

Next we briefly devote also few words for other amphibian typical features, mainly on the diversity in their reproducing. First, there's this exceptional case in point in form of the South-American mouth-brooding frogs. In their case (the male) frog carries small tadpoles/froglets in it's vocal pouch, also providing nutrition them, and from where the fully developed little frogs then emerge.(Halliday-Adler, p 27-28). Mouth-brooding frogs include at least the species we find presented with the name Rhinoderma darwinii (VU) - listed so from it's observed decline in part of range, though mentioned still rather common on some places (acc. its IUCN Red list data sheet on Rhinoderma darwinii). Most frogs, however, do reproduce by their more common manner, laying amounts of eggs on water sources (which usually are fertilized externally). Especially the rain forest species, however, have developed additional strategies to their breeding and protection of the juvenile.

A manner used by many from tree frogs is to deposit eggs on vegetation/leafs overhanging the water, (also typical to the reed frogs, a group in the African arboreal frogs with over 120 species)(Spawls-Howell-Drewes 2006, p 184). The eggs later drop for the water where the tadpoles then start their metamorphose (for a frog). There's also species whose eggs are developed in certain 'foam-nests'. When the edges of the nest dry it falls for waters below. The inner in the foam nest remains moist some days, allowing the tadpoles to emerge in it. In some cases the creation of the foam nests involves lot group-behavior by frogs, the foam released by female frog(s) and forming the nest between leaves, which is then 'hardened' from it's outer surface by several male frogs hangin' on beside nest's edges.

Further more, there's as well many that use some alternative method like depositing them eggs in the burrows dug near the edges of the seasonal (water) pools - after the rainwater floods for pools and finally enters burrows, tadpoles swim for the open water.

(Like in the exemplary case from (East-)African Guinea Snout-burrower, interesting looking species from genus we find provided with the name hemisotidae, mentioned at Spawls-Howell-Drewes (2006) book). (Species pic above)

Somewhat more especial, may appear the reproduction of some of the earlier mentioned tiny (S. American) Poison dart frogs (from genus Dendrobates), species that live mostly within the leaf litter on level of the rain forest floor. Fx, in the case of some of the Strawberry poison frogs (D. Pumilio, LC), the frog first lays its eggs on leaves and carries the hatched tadpoles (under the protective foil on frogs back) to the axils of certain plants, or, to cloaks of trees in some cases. These contain small level of water in which the tadpoles grow to small froglets (number of other species also live in these aquatic micro-environments). The female frog also feeds tadpoles with the unfertilized eggs. Some Madagascar frogs are mentioned with somewhat resembling manner at their reproduction and 'parental care'.(Halliday-Adler 2002, p 28-29) Yet, further another exceptional method (in the variety of frog breeding) is maintained by some another South-American species that we find presented as 'Marsupial frogs', or Rana marsupial (Gastrotheca ovifera, EN). In that case eggs are first directly fertilized and each is placed to a certain protective 'pouch' on females back, where they remain in moist and pretty safe until emerging as fully developed froglets from there - and the juveniles when 'born' seem to bop directly from the frogs back. The species also is mentioned endangered acc. it's IUCN listing (IUCN Red List data sheet; Gastrotheca ovifera). Various other frog species carry their fertilized eggs on the adults back (/or, fx attached beside frogs legs like the Midwife-toads). Most usually the developed tadpoles are just dropped for water to develop. (I guess this variety of frog breeding methods only presented by brief look for the topic in above sentences... but, seems quite adequately covered, so let's leave it for that now.)

Finally, this kind of gallery of frog wonders and especial features cannot do without mentioning the 'flying frogs'; A species group comprising from the Asian (arboreal) forest frogs, that glide long distances (from tree to another) with particularly developed formations in limbs (webbings, spread for like parachutes/gliding surface, that 'permit the kermit' for “fly”, very seemingly) Among these we find a species provided with name Rhacophorus nigropalmatus (LC); or Wallace's flying frog after A.R. Wallace, 19^th century naturalist explorer also presented in our recent post. (The Indo-Malaysia islands Wallace journeyed contain various animals first recognized by Wallace and therefore named after him ; from the birds most renown are probably the Moluccan Megapode (Eulipoa wallacei, VU) and a paradise birds species Wallace's Standard Wing (Semioptera Wallacei). He also describes both quite thoroughly in the book.) For the flying frog(s) Wallace also devotes a few paragraphs, though far less in lenght than descriptions from the above mentioned species - But, it wouldn't feel too surprising if some frog species would also be named after him. In overall the Rhacophorus frogs belong for the Afro-Asian tree frogs, and in addition to this example mentioned genus/group contains number of other glider frogs. Recognized as separate species only later, perhaps. (Pic below; Wallace's flying frog)

But, for now we'll have to cut this in brief, since this only was meant to present some ordinary examples from that variety and overwhelming richness of life - From the amphibians in their about 6300 recognized species in existence worldwide and some even mix together and/or are not clearly differentiated from near similar/co-species. Many of them vulnerable to various threats, Climatic Changes the most often mentioned of those. Anyone can also easily search further details from the mentioned few species we were able to present in this (and from various other; fx, nothing we were having time or space to present from the vocal communications of the frogs, or about some other things - like from the species especially adapted for watery environments/lifes; the leaps and bounds of the frogs; not much anything from most of the popular families – like the arboreal tree frogs of the Central-/South Americas noticeable from them slender and curious looks, and most often presented in the natural books pics...And whatever else has recently been researched from amphibians and their evolutionary histories, obviously.)

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Note:

1. Species also presented with the CR listing, since both seems been moved to the category/status of EX rather recently. (In the IUCN fact sheets listed as extinct about the turn of the century. But, what a happy surprise it would make if some surviving specimen/individuals still would turn out to be found, somewhere, even that it seems very unlike possibility.)

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Sources/other information:

La Marca - Manzanilla 2004. Gastrotheca ovifera. In: IUCN 2009. IUCN Red List of Threatened Species. [Version 2009.2.] <www.iucnredlist.org>. Downloaded on 19 November 2009.

Ed Meyer (et al) 2004. Rheobatrachus silus. In: IUCN 2009. IUCN Red List of Threatened Species.[Version 2009.2.] <www.iucnredlist.org>. Downloaded on 19 November 2009.

Jean-Marc Hero (et al) 2004. Rheobatrachus vitellinus. In: IUCN 2009. IUCN Red List of Threatened Species. [Version 2009.2.] <www.iucnredlist.org>. Downloaded on 19 November 2009.

Carmen Ubeda (et al) Rhinoderma darwinii. In: IUCN 2009. IUCN Red List of Threatened Species. [Version 2009.2.] <www.iucnredlist.org>. Downloaded on 21 November 2009.

Halliday, T. -Adler, K., (2002), The New encyclopedia of Reptiles and Amphibians. N.Y.

Spawls-Howell-Drewes, (2006), Pocket guide to the Reptiles and Amphibians of East Africa. London.

Magnetoreception at (some) amphibians;

(Both studies from The Journal of Experimental Biology)

Brassart, J [et al], 1999, Ferromagnetic material in the eastern red-spotted newt Notophthalmus viridescens., (JEB) Vol 202, Issue 22 3155-3160

Phillips, John B. [et al], [2002] `Fixed-axis' magnetic orientation by an amphibian: non-shoreward-directed compass orientation, misdirected homing or positioning a magnetite-based map detector in a consistent alignment relative to the magnetic field? , (JEB) 205, 3903-3914

[ Pics at the text from Halliday-Adler book; except the Guinea-Snout burrower from Spawls-Howell-Drewes.]

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Intermission (III.) / Anniversary 100th post

Celebrating mildly this important land-mark (the 100th post) on the paths of the MuleSkinner Blog, the cake is prepared and served (however, since we have no time for celebrations, this post is instead cooked of folk-tales and wonders of the nature...)

...Our butterfly-series now completed, we nevertheless devote a few lines for them here. Species is considered to be one of the most cold resistant in the world (or indeed it's larvae which overwinter). It's the Scarce Copper (L.Virgaeuris). In butterfly's populations of the most northern area (which reaches beyond the Arctic circle - probably quite northern range for a butterfly), the larvae has capability to produce glycerine/or, glucose (apparently, the same compound as used in the cars as fuel antifreezer). A single larvae produces amounts of over one third from it's own weight permitting then the survival through most extreme winter colds. In the spring when the warms arrive the liquid disappears from it's body systems and later metamorphosis takes place. (It also is common at some mountain ranges on other areas, whether these also have developed same method for overwintering wasn't mentioned...seems less probable, somehow)
...and perhaps it's not even sole example of that kind, but anyway pretty exceptional and not the less surprising than anything we find from these natural wonders...

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The (folk-) story part is actually good old tales from the Brer Rabbitt. (Whether the story's really folk-tales or has been invented by some artist at Walt's firm I have no idea, 'cause I only have it at the old W.D. children book series. But it's named as Brer Rabbit and his Friends in the original book.)

In this ordinary story, the Brer rabbitt fools with the Fox and the Bear as he usually does (Fox and Bear, as usually, try to catch him for the dinner). However, they have the idea for to make a rabbit replica from glue and when the (Brer) rabbitt then meets his 'double', he gets angry because that is not answering his compliments. Soon after, from hitting the doll, all his limbs and finally the whole rabbitt is stuck with the glue. Fox and the bear think they've finally catched Brer Rabbitt...but as usual it all ends well for the rabbitt, since being clever he soon tricks them to throw him for the brier (bushes), where he lives.


(Having not familiarized myself with rabbit lifes and ecology, I've always wondered if it's just in the fairy-tale that the rabbit is homing in the briers? Or do some of those actually inhabit the bushes? Of course, that's rather secondary of importance; in the story seems like he does. (picture below) (W.G.)

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Species Endangered (MS-Blog Series from) XI / 09

White-backed Woodpecker

Class: Avia

Order: Piciformes

Latin name: Dendrocopos leucotos (leucotos)

Range: Wide but scattered range; appears on suitable forests across the Euraasian continent and Asia (and as far east as Kamchatka And Sakhalin).

IUCN: Not listed(probably), but species locally endangered in some countries /CITES: -

(approximately a 2000s situation)

The birds have been remarkably few of appearance in preceding posts at these series. That absence may have been from the wide variety of available genera, but likely is also resulted from the difficulty to select representative example(s). However, this part generally focuses on woodpeckers and for the lesser extent other (endangered) birds. Also makes an example from locally endangered species (Acc. to information we find, the White Backed-Woodpecker – with the several subspecies - has in overall large range and it's therefore not counted among the particularly threatened, birds global population estimated closer one million individuals)(Birdlife Internat., 2009 species fact sheet) Locally endangered animals in various countries of course are not limited to birds, but there's examples from as various as crocodilians, insects, and others. -> Bird pic beside; Dendrocopos leucotos.

Like noticed (in the earlier posts) the land birds, particularly those endemic to islands and habiting the restricted ranges, contain many that historically have been affected from human purposes. In spite of that, (important to notice as well) the birds also represent most widespread from the animal classes in the world; excluding humans they solely inhabit all eco-regions (ie continents), including the Antarctic and various Oceanic islands.¹ And that being so originally, even without human accidentally caused/intentionally brought species introductions. The especial features for birds aren't limited just in their capability for flight, but there's other evolutionary 'novelties' like their feathers that make birds (often) better resistant to cold and wet than most other animals. According to current knowledge (I suppose) feathers are believed having evolved for birds preceding the capability to fly. That, and the birds having stable body temperatures (like mammals) make some important factors having permitted their spreading almost everywhere in the world.

From the origins of the birds there's nowadays probably a lot varying research/studies, if not too stone cold complete detailed theories. However, since this part only focuses for woodpeckers, we just refer for their origin and pasts (perhaps in some later post more from bird evolution can be presented). Woodpeckers (The main group, Picidae, consists of wrynecks, piculets, and 'the real' woodpeckers) are believed by earliest origin to date as far as the early Eocene period, roughly 50 Million years ago(Mya), although the mentioned still extant sub-families appear believed younger; In the fossil record, the earliest forms from these being found from about the mid-Miocene, ca 15-10 Mya.

Generally woodpeckers are birds adapted for various different forest environments – which also makes an argument on behalf their selection here. There's about 200 species in the Picidae. In addition to largest part adapted for life in forests, some variation and exceptions appear; fx, there's species inhabiting the deserts (and making their nests on cactus, fx) or even some adapted for more unusual habitat for woodpeckers (fx those having abandoned trees and making nests on the ground, at burrows). Usually, again with plenty of exceptions and specialization, many woodpeckers eat small insects they seek from the suitable trees (typically fx aspen, birch in places where these appear most common from broad-leafed trees). Woodpeckers also hollow their own nests in the trees. When abandoned, those nests are also often used by other bird species. But, like many animals, also the woodpeckers are most numerous from the species that appear in the tropical forests.

Like is commonly known, most real woodpeckers are noticeable from their impressive behavior of 'drumming' (or pecking), a practice that also serves to signal other individuals their territory range (or some other purposes...) That is indeed very impressive sight, seeing a bird hammering with repeating rapid series of pecks high at the tree top. Because of that they are also sometimes easier locate in forest, even though they tend to avoid human watchers eyes flying less usually over open spaces or rarely at the level of the lowest twigs - However, again there's exceptions to the general rule and various species typically feed on insects, often ants, they seek on the forest floor level. Woodpeckers brain-cases, particularly strong necks and bills are especially evolved for pecking, that permitting them also excavating their nests. As another adaptation the woodpeckers feet is somewhat specially structured for to keep it firmly stable when pecking , fx.

From other typical features, also in our exemplary case, is them being often birds that keep rather permanent territories, only some specimen occasionally wandering for more distant areas – Which perhaps makes them somewhat vulnerable for human caused habitat destruction when compared with birds known more adaptive to various environments that sometimes may effectively enlargen their ranges; (Fx, from quite opposite behavioral practices we find an example of the common Starling (Sturnus vulgaris) which has been human brought to various continents. In the case of it being introduced for the New York Central park at 1890s with population of about 100 birds, it was in just about 50 years found having spread on the ranges from Mexico to Canada. Although, a bird that commonly habitats urban environments it's not found spreading as fast in some other region.) (Perrins, 1990) But there's also birds that happen take benefit from human activities more directly; like some seagulls that eat also human left-overs - and appear commonly on harbours, wastelands, where there's plenty of food for them. Returning to woodpeckers characteristics, we find them typically local birds, often overwintering in their living region (yet there are species which migrate even for great distances). As from outer appearance (many) from the actual woodpecker species are noticeable from black/white main colors, with the red or yellow area on the crown of the head. Sexual dimorphism is also typical, males having somewhat stronger coloration and usually being slightly larger by size.

Even though these birds (Picidae) show variety of genera, many adaptive to different environments and probably most species not threatened, there's of course some that are: fx from the largest the Ivory-Billed Woodpecker (Gampephilus picus, CR) are mentioned among most endangered birds in the world (Imperial Woodpecker, as well, that for some time seems been considered probably extinct). From the reasons to the decline/scarcity of the former mentioned - in during 20^th century - we find (not surprisingly) the reduction in the suitable habitat areas it favored. For comparison, it's noticed fx that some other from the larger species, like the Black Woodpecker (Dryocopos martius) and its american 'cousin'/resembling species(both about the size of the crow), are still rather common. However, both appear at various kinds of forest, although they also need to maintain large territories to find adequate amounts of food. From the other large species - actually mentioned largest from the still common species - there's one East-Asian species (which the source presents with name Great Slaty Woodpecker (Picus mullerensis, LC). Although, it's also mentioned mostly inhabitant of the natural forests. Various other species that appear on more limited ranges may be more or less threatened, but for this we've not checked other examples.

(Not necessarily especially related to any of the preceding examples– but according to some studies the existence of deadwood in their habitat area was found favouring some woodpecker species/increasing their populations.)

From the woodpecker selected as particular example in this post, like said before, it's not considered globally endangered (and not listed in the IUCN Red List, therefore). However, similarly like it there's various animals under the threat of disappearance in some countries, even that they may be more common in the other. This typically also causes some difficulties for their protection. Fx, some migratory birds may be threatened in their usual region, while they're not always considered so in the countries along their moving route/overwintering area. Because of that, there's intergovernmental treaties, like the UN-backed Convention on Conservation of Migratory Species of Wild Animals (CMS), also known as the Bonn convention, aimed for protecting the migratory terrestrial, marine and avian species throughout their ranges. Also, there's wild animals, whose population in some place may be migratory while the population(s) on the other region/country appear not - like in the case of Japanese Crane (Grus Japonese, EN), which has populations on Asian main continent and Japan.

White-Backed Woodpeckers (that are not migratory) appear rather common also, although they are mentioned on slight overall decline. In the Europe, they can be found usually in places where there's (often the conserved) larger woodlands and/or lower mountains elevations with sufficient forest cover. The bird probably has quite steady populations on some east Europe countries like Czech, Slovakia, Poland, Bulgaria, comparable in numbers (sometimes) for those of fx the Black woodpecker – Although, neither on this basis seems to occur close as abundant as the Great Spotted woodpecker (Dendrocopos major) in some areas <- bird pic left (It closely resembles Dendrocopos l. , though the Dendrocopos m. is slightly smaller in size, fx - and actually I'm not quite sure if I could easily tell one from the other even at close distance). In some other countries of the South-/East- and Mid-European ranges White-Backed Woodpeckers usually appear with somewhat more varying populations. (acc. Birdlife Internat., 2009 species fact sheet). - Since the map doesn't present us current estimates from it's northern range (Scandinavian countries), we'll only basing following on other sources from about 1990/2000s situation; It perhaps wasn't originally there such frequent in the first place, because this makes the far northern edges on the global population. Yet it was relatively common until recent times. Since about 1950s it was been in apparent decline (in Finland from about some 500 breeding pairs to quite recent estimated 50-70, and in Sweden maybe even more declined, the remaining populations limited to few areas. In the Norway, mostly appears closer the Atlantic coastal side where its more common – possibly because the climates and ecological regions there appear slightly different and more favorable to it, I would suppose)

Main reason (/most affecting single factor) for the noticed decline has been the disappearance of larger deciduous forest areas in mentioned regions. As result it's also believed probably having lost parts of its former territorial range for the Great spotted woodpecker, which more easily inhabits also the coniferous forests. In comparison the Dendrocopos l. is more demanding from it's diet and mostly feeds on certain insects that it digs from broad-leafed trees like aspen. Therefore it needs particularly large ranges of the broad-leafed forests and these were continuously found reduced in during 20^th century, largely because of the forestry economics favoring more timber productive coniferous trees.

So, this presented mainly as an example from locally endangered bird, but also from how any human forest use can change the conditions for the species adapted to particular habitats, fx. In principle the forestry management affecting it's decline (mainly) was maintaining - in some ways, acc. to levels of the time at least - rather sustainable practices; fx about same amount of the trees that was felled was (about) yearly planted, number of timber taken controlled in overall. (There's always other changes from the forestry use, fx the machinery 'mutilating' the ground, even though the long-term effects from that are often considered/argumented only limited. - Anyway, as an example from the locally endangered species this perhaps doesn't present a case too much generalized, but from human use and caused changes in the environments this is probably more typical and not at all unusual example.)

...Further from this, view the MSW book recommendations #28 (W-G.)

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Note:

1. Although, this point-of-view doesn't take into account marine species, since they are usually presented separately from quite logical reason. In Antartica there's plentysome regular marine mammals as well as the fish and some other habitants of the seas. Penguins of course are most well-known of the birds (them being terrestrial birds) but there's birds nesting in some coastal areas fx. And perhaps various (pelagic) species.The human inhabitants are limited to people at research stations (even if these are permanently populated nowadays, even).

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Sources:

BirdLife International (2009) Species factsheet: Dendrocopos leucotos.

Downloaded from http://www.birdlife.org on 13/10/2009

Perrins, Christopher M. (Ed.), (1990):The Illustrated Encyclopedia of Birds.

(Wikipedia ; Picidae/White-Backed Woodpecker)

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Muleskinner Book recommendation #22

Malay Archipelago; The land of the Orangutan and the Bird of Paradise

(by A. R. Wallace)

(orig. p. 1869; the refered text from Gutenberg edition, v. 2008)

[Recommendation 12/2009]

These series of recommendations so far (not intentionally of course) have omitted any travel books and journey stories; This 19^th century 'travel book' (or more precisely tale from naturalist expedition) is for the replacement of the shortage. Also, we've included this far only one biography, which also accidentally happens to present a 19^th century text. (However - according to my calculations the appreciated reader could quite as well already have received recommendations from at least another biography and from few other comparable naturalist/past conservation classics. The preceding said, of course, with considerable respect for the great generosity of that undeniable, invisible, inconsolable MSW despot...and just to keep our readers informed from those tactics of coincidences and depression.).

Turning our attention for the book selection here, the Malay archipelago; We find it from general form and features having some elements common with earlier texts/books selected from the same century – fx, it was originally published in editions of two volumes like also was the earlier presented Bronté-biography. From its plain contents recommended text in this case appears quite heavy reading(at least the Gutenberg-edition available for us here in MSW and therefore the one presented/discussed), because the sheer size of the book, concise text making over 400 pages printed with compact paragraphs. Probably makes the reading experience slightly 'lighter' if checking the book from the Papua-web online edition. - from the reason that it also contains original pictures and drawings of Wallace (1823-1913). The books rather well-known naturalist classic so probably its been reprinted several times since its 19^th century publications. Should be available on Google-books as well, with most likehood.

Book itself is counted for the most influential books ever written from region it describes. As well, it's usually mentioned among the most important early scientific descriptions from the tropical regions, inspired by the Darwinist theories of the time – for the 'Darwinist' view from nature and his theory of evolution was just gaining ground in those times and had it's early supporters, Wallace among others. (Actually, Wallace with his own observations fx in this book, and also at various other writings, is often nowadays mentioned among the originators of the theory from natural selection, sort of 'co-inventing' it with Darwin. Although he from modesty, as is also claimed, didn't ever demand any honour from that and mostly refers to Darwin when mentioning the theory in this book. Anyway, they were sending letters to each other, which seems, supposedly, have inspired Darwin to publish his 'revolutionary' view and perhaps encouraged him other ways too.)

According to some views Wallace was also sort of an outsider among the (natural) scientists of the time, even among the 'Darwinians'. For obvious comparison appears the journey story by another similarly renown naturalist traveler, Henry Walter Bates (1825-1892) -on his Naturalist on the River Amazon (p. 1863). Both spend several years in the tropical jungles collecting the animal species, part of that time together (Bates is well-known from his studies of mimicry on the basis of examining that in the butterflies, generally known as the Batesian mimicry). Compared to journey memoirs of Bates, Wallace's expedition tale draws from rather more various topics; in addition to the naturalist observations and description of the landscapes/places, there's views and theories from the archipelago's geologic prehistory (them being quite correct on the basis of the knowledge he might have been aware at the time, we find it stated), descriptions from the cultural practices and also from constructions and architecture styles in local villages and, also from plantations that already at that time were cultivating various fruits and other products (like cocoa, sago-palm, etc), many of those also exported - and as well from Wallace's personal experiences on the journey (also from the troubles and obstacles like occurring diseases, fx).

According to later view (apparently) it seems stated that although Wallace didn't receive much public acclaim or not wished to take too much part for that hotly debated question of the time (from theory of evolution), his views in this book made established the general concepts from the natural history and evolution of the particular species found on different islands at the archipelago. Since the islands present from animal variety and nature the 'Asian' and 'Australasian parts, divided by 'deep sea line', it has everafter that usually carried the naming 'Wallace's Line' (or the Wallacea line). – That being only a general (limited) summary from the main thesis in the book, which, besides, also discusses the earlier mentioned assumptions from geologic prehistory of the archipelago. Related to preceding, Wallace's collection from animals is often praised among most 'complete' natural historic collections in museums (containing birds, insects, beetles, etc from the journey described in book.)

From historical backgrounds we can briefly notice that already in the time when Wallace was making his journeys (1850s and 1860s) we find the archipelago been under ongoing change, although probably it perhaps was bit less directly affected by colonial politics of the time than some other areas (like the India, China, fx). Region probably remained far longer as remote district (even Singapore remained rather isolated and distant part at the British World Imperium until the latter part of 19^th century) containing some smaller independent kingdoms and native rulers. Also, the population consisted from rather varying entity of inhabitants and by-passers. Likely therefore, also the nature of area remained from larger parts unexplored until the turn of 2oth century. The variety of people in region (in addition to indigenous habitants) included European colonists from several countries like Portuguese that had been the earliest acc. To Wallace, many territorial regions having later then been obtained by the Dutch and the British. Also other nationalities from somewhat earlier origin (fx he mentions the Chinese traders, ao.). Wallace comments occasionally on conflicts and various problems from robbery and pirates, and also mentions revolts against the colonial rule in some regions, but one gets the general impression from rather stable conditions on many places he was travelling, although he sometimes mentions the prevalent possibility from the emergence of unrest.

Wallace's trips were headed for exploring 'wilderness', but he journeyed from towns/ports that had been established on various islands and he casually did travel on transportation ship routes (Also, on the routes he uses, steam boats fx, were already carrying mail and transporting traders and goods between the different ports. His remarks from those give the impression from rather comfortable travels on some routes.) Of course, he spend also long periods in the villages and places from which many were less frequently visited by earlier (European) travelers (or not at all). As the typical European high-class (in towns especially) usually lived separate from the original inhabitants or the 'native classes' in the colonies, Wallace's expeditions possibly appeared somewhat more peculiar journeys for his contemporary countrymen too. On the basis of the preceding, one can then (perhaps) even consider him as a 'Darwinist adventurer', although that by most certainty would have been strongly rejected, himself finding that of naturalist more suitable description.

Contrary to these many praises from the exceptionality of Wallace's 'historical character', it can be also stated that even if he might present some unconventional persona, his writing (at least in the text refered here) often holds much of an 19^th centurian attitude (fx, about cultural differences most typically). From current perspectives, some 150 years later most of that seems just aged, if not reflecting the colonialist view. But that was my general impression from reading the book (however, fx in the final part of the book he critizes any opinions from the social conditions of 'the civilized world' approaching perfection.) Same can be said from some of his actions that seem not too much enduring viewed from our times. The modern reader fx cannot avoid rather strange impressions and astonishment from his description of hunting Orangutans in the jungle (Wallace was committed to supplying several of those for natural collections - mostly for museums, I suppose - to ensure funding for his journeys.) First he lists the various efforts to fulfill that task at Borneo, and next after turning the page, there's descriptions from his subsequent untiresome efforts to save and raise in captivity the infantile of the ape killed - And apparently not finding any contradiction in those deeds. On the light of the current conservation problems and discussions (the species nowadays having become endangered from the leveling and disappearance of its original forest habitat) his doings feel somewhat confusing, probably even more than would be the case otherways. Considering also the time-gap in between present and Wallace's times (one and half the century), it can be noticed that probably our own times and its sciences and 'methods' seem as much odd when similar periods of time have passed.

But, since there's also quite a lot more in the book than descriptions from animal hunts (mostly those are focused on birds and insects he collected) we can finally include few interesting paragraphs from its contents in this recommendation. As said in the beginning, books rather lenghty volume to read, even if the narrative touches plentiful things in addition to the main natural history theme. Here of course can only rather brief exert be presented. The selected example is from the conditions Wallace was working at; it's not presenting a general description, only from his staying on certain place, but gives us some view, anyway:

"My collecting operations here were carried on under more than usual difficulties. One small room had to serve for eating, sleeping and working, and one for storehouse and dissecting-room; in it were no shelves, cupboards, chairs or tables; ants swarmed in every part of it, and dogs, cats and fowls entered it at pleasure. Besides this it was the parlour and reception-room of my host, and I was obliged to consult his convenience and that of the numerous guests who visited us. My principal piece of furniture was a box, which served me as a dining table, a seat while skinning birds, and as the receptacle of the birds when skinned and dried. To keep them free from ants we borrowed, with some difficulty, an old bench, the four legs of which being placed in cocoa-nut shells filled with water kept us tolerably free from these pests. The box and the bench were, however, literally the only places where anything could be put away, and they were generally well occupied by two insect boxes and about a hundred birds' skins in process of drying. It may therefore be easily conceived that when anything bulky or out of the common way was collected, the question "Where is it to be put?" was rather a difficult one to answer. All animal substances moreover require some time to dry thoroughly, emit a very disagreeable odour while doing so, and are particularly attractive to ants, flies, dogs, rats, cats, and other vermin, calling for special cautions and constant supervision, which under the circumstances above described were impossible.

My readers may now partially understand why a travelling naturalist of limited means, like myself, does so much less than is expected or than he would himself wish to do. It would be interesting to preserve skeletons of many birds and animals, reptiles and fishes in spirits, skins of the larger animals, remarkable fruits and woods and the most curious articles of manufacture and commerce; but it will be seen that under the circumstances I have just described, it would have been impossible to add these to the collections which were my own more especial favourites. When travelling by boat the difficulties are as great or greater, and they are not diminished when the journey is by land. It was absolutely necessary therefore to limit my collections to certain groups to which I could devote constant personal attention, and thus secure from destruction or decay what had been often obtained by much labour and pains.“ (Paragraphs from Vol 1; chapter X)

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Some additional/co-reading

...That may appear worth checking (fx) if interested for more current topics:

Daws, G. - Fujita, M., (1999), Archipelago: The Islands of Indonesia: From the Nineteenth-Century Discoveries of Alfred Russel Wallace to the Fate of Forests and Reefs in the Twenty-First Century.

(Examines fx the present day deforestation issues basing on Wallace's 19th century observations)

Sheil, (D.), [et al], [2009?], The Impacts and opportunities of palm oil in Southeast Asia ; from CIFOR (Center for International Forestry Research) (Pdf)

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Species Endangerd (MS-Blog Series from) / X

The Coral Reefs

Class: Anthozoa

Order: Various (sub-) order/class

Latin name: -/-

Range: Generally the reefs exist mostly at warmer latitudes/on Oceans like Pacific, Caribbean, and Red seas (The largest and most renown probably are Great Barrier Reef (near Australia) and Coral triangle (on Indo-Malaya archipelagos)

IUCN Status: Not listed as they are actually marine environments...But globally threatened.

CITES: Not checked...But several coral species/coral polypes probably prohibited from collecting.

(about... 2000's situation)

There's an unestimated amount of life-form and species at the Oceans of the world. As our original purpose in these series was represent also some examples of the fish (sometimes said that contain procentually the largest number of them include for the threatened species), would have been suitable to present at least few of them. But, we haven't too excessively time on this and, possibly, that would also have required having more particular knowledge, ao. So, on this basis it's only logical selection to select the reefs – and they well represent the variety of life of the seas. (Even more so, since some estimates seem say/predict that reefs could suffer further 20-30 per cent loss at just during following 30-40 years time).

Like renown, the life originally begun on seas and the corals as well have existed through distant periods of time. Nowadays they're probably more threatened than ever before during their existence through several past millions years. Although, on some previous periods the reefs have also undergone periods of their almost complete destruction (like larger parts from marine life, in during the so called former mass extinction events). Yet, they still survive on our times. So, on the basis of this, the modern man-made threats considering it's no underestimate if we say them (reefs) nowadays could classify – on similar category as the formerly listed animal species examples – for the EN (Endangered); however, on criteria of their histories of slow gradual growth and larger parts of marine life they sustain, classification as Critically endangered would, perhaps, appear no less correct and quite justified.

(Whatever the opinion of that - feels maybe little like drawing lines on water - the Oceans in general are source of the uncomparable diversity of life, multiple times that what exists on lands. And the reefs obviously form some of the most impressive part of that.)

Contrary to sometimes common belief, the corals are organic animal life-forms (not plants or rocks). They often appear form large areas with complex structures which have in time grown for the known oceanic reefs, particularly on warmer latitudes, and usually at areas closer the (shallow) coastal sea. (The Coral Triangle alone is estimated to contain about a one third from area of all coral reefs at seas.)

The reefs provide important and flourishing environments for greatest number of fish on most anywhere, for other animals as well, non-vertebrate and fx the sea plant. It is estimated that closer half of the fish living on reefs are dependable on the existence of corals for food, shelter and also on their reproduction. Seems stated as well that the reefs probably support highest biodiversity in the world (it been occasionally estimated that they possibly support about a quarter of all the marine species found on Oceans.) For humans they appear important on uses as fishing areas and of other subsistence needs, ao.

Since any of that oceanic life would appear probably too vast an area to represent on this (probably we haven't too much of a knowledge either), it suffices us list some species that appear to commonly presented favorites at marine biology (TV-) series. (But as that life of reefs is said so abundant and fx colourful, the films and pics, like often noticed, only show a pale reflection from it. Maybe any hobbyist of the deep sea diving, fx , would have a lot more catching stories to tell...) Anyway, for some most usual species presented on those and, perhaps more typical on certain reefs, are the colourful Clown fish (Amphirimidae) – they are renown of the manner of living at rare kind of symbiosis with the Sea anemones (the clown fish receive cover and protection of the anemones, but the 'sea plants' tentacles can be appear danger for some other fish, occasionally it even catches the prey from the clown-fish, it said).

As well as the fish, there's many colourful and numerous species on the 'marine plants' (but all of those in the following actually are animals adapted to living on sea bottom). Fx, for the better known species from echinodermata (apparently) belong also the Sea lilies (of the genus crinoidea), and as well the holochteroidea. The former especially appear numerous on coral reef, and they also represent species that move slowly on the sea floors. As well, somewhat similarly species adapted to various depths at seas, but also some usually seen on coastal reefs, are the Sea urchins – there's at least about 1000 different species of them, several are common on reefs (their thorns can be of considerable harm and it's better avoid stepping on some). However they're also very enduring animals, some species dig - with the patience, the process lasting many years – their places of stay on fx rocks  surface (and even at steel balks on harbours). Along with the mentioned, there are countless number of the fish, marine mammals and the reptilian; dugong (probably), manatee, sea turtles, fx, etc.

The main straight-forward threats of the reefs consist fx over-fishing and other human caused harms. Over-fishing can (very potentially) affect the reefs natural ecology and cause changes at species relations which then maybe further result for changes at their ecology. However, humans have fished on much of these places as long as they've practised that elsewhere, so the most harmful impacts are perhaps newer from origin. Some of those are poison fishing, use of paralyzing chemicals to catch collectible species and fishing with explosives (where often the reefs coral and other species get destructed as well). (Both practices sometimes said common on some areas at the Coral Triangle, ao.) Similarly, there's more typical pollution and fx the agricultural pesticides gathering on water flowing to coastal waters, etc. Also, the building projects on coasts, often cause destruction of reefs as co-result. And other things, oil spills and ships traffic, the garbage and thrash thrown on waters, etc.

Yet, the 'newer' noticed harms, and what may (potentially) threaten most reefs on the oceans, is said possibly to emerge as consequence of increased the GHS-emissions. As consequences within accumulation of atmospheric gases that dissolve on seas, the acidification level of waters follows to grow, or precisely leads for the reduction on Ocean water Ph. That slows  growth of the coral, and possibly can cause their complete destruction (on places at least). Or, so that was said some time ago, mostly it been said affecting for calcification forming organism, typically coral polypes. How severely and how rapidly such effect could take place may be is not yet that well known, at least it's somewhat unsure how the scenario may appear on different sea environments , etc. But even if it not yet proven a scenario, some of the adverse effects of the sea water warming are found form the coral bleaching, which is known having caused general degradation on corals and their disappearances from (more or less large) area. Although, the phenomenon also is relatively new from it's (known) origins, and wasn't yet too much recognized until about the 1970s.

Because there's probably emerged further knowledge from many of the above aspects (that we've had no time to check), it is advisable and easy to view that on elsewhere. Anyway, according to what we find said, the reefs appearance are generally believed to change from their current days form, resulting most because of the warming (at some time-scale). Some of the changes, and as main disadvantages mentioned may (likely) be the losses on their protectivity against storms impacts and the reefs recreational value may also reduce and/or lead for loss in the fisheries.

It's also said some coastal eco-systems formed by the mangroves and seagrasses are known to interact and with reefs to some level, and somewhat dependent of their healthy conditions, on them too. Mangroves on coastal areas have, during some recent decades, been destroyed on many areas and/or been turned for human production needs, aquacultures and agricultural use, ao. They are said some of the most heavily stressed (tropical) coastal areas. But it's probably beyond our understanding how much many of mentioned changes (so far) have affected the reefs existence, and likely there's also some newer knowledge been generated from these things. Anyway, the mangroves and seagrasses on coastal areas are said being important carbon sinks, comparable to role of rain forests on that (even that they consist much smaller geographical areas).

More generally appears that the seas, been considered as filters for all kinds of pollutants longer times until our time, often reveal the real damages only when some of that emerges to be seen as more visibly seen as problems and destruction...fortunate aspect may be that seas generally make largest parts of the worlds surface area, so they also still contain much what has prevailed (even) outside human purposes and efforts to make uses from. As the reefs ecology and adaptavity is not too well known it's also possible that them may appear more durable, of some forms or at areas. However, they're also often noticed probably most vulnerable eco-systems of the seas for effect of predicted climate change. Unfortunately them appear also the most flourishing, or most easily reachable part of that flourishment for humans. Humans, of course, have all the possibilities to change much of the past false ways on their uses natures for the better (and for more enduring ways).

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