COMMON HAMSTER (Cricetus cricetus, Linneaus 1758)

Common hamster. Photo by Katanski, taken from Wikipedia.

Common hamster (Cricetus cricetus).

 

Status – Least Concern.

 

It might seem strange to be writing a threatened species blog piece about an animal with the word “common” in its name and, yet, the common hamster is far from being as common as it once was. Indeed, the IUCN still categorizes the species as Least Concern, even though dramatic population reductions and localized extinctions have been recorded in practically all of the countries where it occurs.  Admittedly, it does have a very broad distribution – ranging from mid-Russia in the east to just beyond the Rhine in France in the west, so that collectively, at first glance, the number of individuals would not appear to call for conservation interventions.  However, the populations that make up this distribution are hardly contiguous, instead being fragmented by agriculture, urban sprawl and road developments.  In spite its rather cute, pet-like appearance, common hamsters were once considered agricultural pests and government-funded extermination campaigns were commonplace in Central and Eastern Europe.  Many populations withstood decades of these campaigns but now, though extermination is largely outlawed, the species is in a more precarious position than ever in much of its former territory.  For example, in France, a tiny remnant population lives amongst the maize monoculture of the plains surrounding the city of Strasbourg.  Government inaction, local apathy and antipathy, and the species’ own biology have conspired to drive the common hamster close to extinction in France [for more on this, see my in-depth article here]. While farmers are not the only group that need to participate more in conserving this species, the greatest challenge appears to be persuading them that common hamsters warrant saving.  This necessitates encouraging farmers to adopt hamster-friendly practices and, of course, providing the incentives (usually financial) to galvanize the necessary support for conservation actions.  Thus, the common hamster is a test case for how we deal with human-wildlife conflict in zones of intensive agriculture.  Can we apportion some of this valuable space to it and those other species tied to our farmland, but that have not managed to adapt quickly enough to intensive farming practices?  Perhaps we should drop the “common” part of its appellation and adopt something else that might better reflect the actual status of the species?  How about “Dwindling hamster”???

BUNYIP EGG FUNGUS (Claustula fischeri, Curtis 1926)

Bunyip egg fungus. Photo by Landcare Research New Zealand Ltd. (available from Wikipedia).

Bunyip egg fungus (Claustula fischeri).

 

Status – Endangered.

 

Yes, even mushrooms need love too!!! Despite that the number of fungal species is thought to exceed 5 million, only 15 species are listed by the IUCN Red List as being Critically Endangered or Endangered, which is clearly a gross under-representation of the number of threatened fungi globally.  Why?  Well, most fungi live unseen (apart from their occasional fruiting bodies), so the old adage “out of sight, out of mind” appears to apply in terms of their conservation.   However, neglecting fungal conservation could prove to be a grave mistake since fungal communities mediate a vast array of ecosystem interactions.  For example, most plants rely on associated fungi in the soil to grow, and termites (which account for a huge proportion of animal biomass on land) need the fungi they foster in their colonies to survive.  The Bunyip egg fungus is a rarely-encountered species from the wet forests of Tasmania and New Zealand. Bunyips are mythological Aboriginal creatures of creeks and swamps, so clearly the common name is a little bit ‘tongue-in-cheek’.  This truffle-like fungus is associated with a diversity of vegetation types, but very little of its ecology or habitats are known.  For instance, it is not known how its spores are dispersed, although bird-based dispersal has been suggested based on its morphology.  The greatest immediate threat to the continued existence of this particular fungus is tourism and recreation activities, particularly mountain biking and hiking trails through the few remaining locations (<20) where it is known to exist.  These forest sites are fragmented and lack habitat protection.  Climate change, deforestation, invasive tree species and fire are additional risk factors for extinction.  Providing adequate protection for a species that is hard to census (since it predominantly lives underground) and occurs sporadically in small areas of less than 10m² will require formulation of novel conservation techniques and approaches.  Indeed, coming up with conservation strategies for fungi in general will prove challenging because: a) their lifestyles are so different from those of the plants and animals on which most existing conservation tools are based; b) awareness of how crucial fungi are in ecosystems is so limited among funding agencies and the public; and c) basic knowledge on the biology of rare and threatened species is so lacking.  Thus, mycologists (experts in fungi) have a difficult but critical task ahead in ensuring that the Bunyip egg fungus and its brethren receive the conservation attention warranted by their fundamental roles in ecological processes.

Socorro Dove (Zenaida graysoni, Lawrence 1871)

Socorro Dove. Photo by Magalhaes Berichard, taken from Wikipedia.

Status – Extinct in the Wild.

 

The name of this bird could not be more apt – ‘socorro’ means help in Spanish! This species of dove was probably endemic to Socorro Island (600 km off the west coast of Mexico), where it is known to have occurred until at least 1972, but now only occurs in aviaries in the US and Europe.  While closely related to the mourning dove Zenaida macroura of the North American mainland, it has a very different call and is more heavily built, marking it as a distinct species.  Why the bird disappeared from its island home is not entirely clear.  Introduction of cats to the island in the early 1970s probably was the last straw, but overgrazing of the understorey vegetation on which it relied by introduced sheep is the factor that most likely precipitated its decline.  Ongoing problems with locust plagues, exacerbated by overgrazing, have impeded efforts to reintroduce the dove back to Socorro. In fact, a plan for reintroduction of the dove has been beset by difficulties.  The captive population in the US has largely become hybridized with Z. macroura, so it is no longer suitable as a source population and attention is now focussed on the European captive stock.  In addition, the discovery of diseases in the captive population has raised fears about releasing birds into the wild and it is not clear that the island’s environment has been sufficiently restored to harbour a self-sustaining population, so the reintroduction project has been repeatedly postponed.  In order to prepare Socorro for the return of its native dove, invasive mammals must be eradicated; this was achieved for sheep in 2010 and efforts are continuing to remove feral cats.  That the future of the Socorro dove lies in the hands of zoos highlights the role that such institutions and captive breeding can play in preventing species extinctions.  However, the recurring problems encountered by the reintroduction programme reinforce that the road from captivity to reintroduction is both long and failure-prone.  Whether or not the Socorro dove becomes re-established on its island home in the Pacific depends largely on the persistence of a few dedicated conservationists that continue to press for government support for the reintroduction programme, despite all the setbacks.  In the face of competing conservation priorities, the plight of the Socorro dove remains precarious and it looks set to remain a species in need of help for the foreseeable future.

Florida Bonneted Bat (Eumops floridanus, Allen 1932)

Florida bonneted bat. Photo by Anonymous, taken from BatFacts.

Status – Critically Endangered.

 

With faces that perhaps only a mother could love, purely nocturnal habits that invoke fear in most people, and surrounded by a host of “old wives tales” that engender distrust, amongst mammals bats have the most difficult task in endearing themselves to the general public. Maybe because they are predominantly nocturnal and so rarely observed, the conservation status of many bat species is unclear.  The Florida Bonneted Bat may be not only one of the world’s rarest bats, but also one of the world’s rarest mammals, with a population of about 250 mature individuals divided among five known isolated populations.  In fact, for some of the 20^th Century, it was considered already extinct.  Despite the fact that the species has been recognised as imperilled for the past four decades, it was only federally listed as an Endangered species in the US in October 2013, further highlighting the inadequacy of the US Fish and Wildlife Service in terms of responding to extinction risk.  Historical populations along the Florida coast were probably decimated by over-development and the associated pesticide spraying to control mosquitos for the burgeoning human influx.  Their low reproductive rate makes it difficult for Florida Bonneted Bat populations to respond quickly to perturbations and so climate change is only likely to severely inhibit their recovery to sustainable growth.  Despite being known to roost in tree hollows, rock crevices and palm foliage, currently no natural roost sites are in use, with existing colonies restricted to attics/chimneys and even artificial bat-houses.  Conservation efforts are hampered by our lack of knowledge on the species’ requirements – while it seems to have adapted to roosting in human-dominated environments, it forages in open areas above wetlands or forest canopies so the species would still appear to need the protection of natural habitats.  As natural insect pest control agents, pollinators and seed dispersers, bats in general play a fundamental role in global ecosystems and warrant our conservation concern as much as any mammal.  Conservationists need to work harder to dispel the negative myths surrounding bats and champion their protection among the general public.

Honduran Pit Viper (Bothriechis marchi, Barbour & Loveridge 1929)

 

Honduran Pit Viper. Photo by Jeff Whitlock, courtesy of The Online Zoo.

Status – Endangered.

 

Perhaps the most difficult of faunal groups to muster broad public support for conservation efforts, snakes in general evoke negative sentiments in most people except the most ardent herpetologists. However, where they occur, snakes are vital cogs in the food web, mostly acting as predators, but also occasionally falling prey to other predators higher up the trophic scale.  And even though snakes are responsible for a number of human deaths each year, they are of value to humans in the control of rodents.  A highly venomous snake, the Honduran pit viper typifies the problems encountered by many snake species worldwide.  This particular species is classified as Endangered by the IUCN predominantly because of its restricted range, occurring in only five locations of undisturbed forest.  Thus, as for most species, habitat destruction represents the most critical threat to its continued existence.  However, the impact of habitat conversion on declining populations is compounded by collection for the pet trade; although admittedly this is becoming less of an issue as specimens are increasingly hard to find due to their rarity, Honduran authorities appear to still issue export permits for this endangered species.  A less heralded impact is the role that a chytrid fungus is having on the prey base of the Honduran pit viper – this disease is decimating the amphibian prey of countless species worldwide and is undoubtedly a major contributing factor to dramatic population declines of numerous snake species globally.  In terms of conservation efforts for the Honduran pit viper, there is little that can be done immediately to control the impact of the chytrid fungus that is having such a devastating impact on its prey.  Instead, our efforts must be concentrated on protecting the last remnants of intact forest in Honduras where it occurs.  In addition, the species should be immediately endowed with CITES Appendix II status to limit trade in the pet industry.  Finally, perhaps the most formidable challenge is to make headway in revising public antipathy to snakes in general by reinforcing their vital function in ecosystems, highlighting their remarkable physiological adaptations, and endeavouring to better balance the exceedingly negative press with positive depictions of snake ecology.

Chinese Giant Salamander (Andrias davidianus, Blanchard 1871)

Chinese Giant Salamander for sale in a Chinese restaurant in 2013. Photo by Micromesistius, courtesy of Wikipedia.

Status – Critically Endangered.

Despite having a rather broad distribution, the population of this the largest species of amphibian (which can grow up to 6 ft in length) has declined dramatically over the past 30 years, primarily due to over-exploitation for food (although it is also a component of some traditional medicines).  Undoubtedly, habitat destruction, pollution, climate change, inbreeding and disease have also contributed to the estimated 80% reduction in the size of the population over the past three decades. Almost blind, it relies on sensory nodes that run along its body to detect the crustaceans, insects and fish on which it feeds.  However, it itself is considered a delicacy, reaching prices of well over €200/kg (almost US$300/kg) and therein lies the threat to its future existence.  Why the flesh is considered savoury is questionable, with reports likening it to bland chicken.  Instead, it is the prestige of eating such an unusual and rare creature that appears to bolster the price on its head.  This has very grave consequences.  Typically, when a species becomes so rare that the costs involved in hunting it are prohibitive, its desirability diminishes in the marketplace.  However, if with increasing rarity, the prestige of having a specimen grows, then the value of the last remaining specimens climbs exorbitantly and so the impetus to harvest the last remaining specimens only increases.  This trend to attach luxury status to endangered species is rife, and a huge stumbling block to conservation efforts.  It is also an indictment of the gross superficiality of the super-rich that are willing to spend inordinate amounts of money on a fleeting moment of sustenance that has nothing to do with taste and everything to do with impressing other status-seeking junkies.  Regrettably, efforts to stem this “fashion” for consuming endangered species have had little impact, and the practice continues almost unabated.  Unfortunately, it seems that we need to rely on shallow super-rich consumers developing a conscience in order to have any impact on the endangered species market, and experience demonstrates this is not likely to happen.

Golfball cactus (Mammillaria herrerae, Wederman 1931)

Golfball cactus. Photo by Norman Dennis, courtesy of http://www.arkive.org

Status – Critically Endangered

I apologise now for the intended pun, but I want to broach a rather ‘thorny’ subject.  It relates to unscrupulous plant collection by gardening enthusiasts and it is an issue worldwide and a problem for a vast array of plant species.  Here, I highlight the plight of the golfball cactus, endemic to one tiny area of less than 1 km² in the Mexican drylands, north of Mexico City.  This rather humble, though pretty little cactus is in imminent danger of being completely wiped out in the wild (over 95% population decline in the past 20 years – perhaps only about 50 wild specimens remaining), primarily due to illegal collection.  The fact that it is a common and popular specimen, widely traded in horticultural circuits, should not detract from the need to act now to prevent extinction in its native habitat.  While it might be argued that reintroduction will always be possible from horticultural stock in that eventuality, it seems rather callous to allow a species to go extinct in the wild just because there are specimens sitting in plant pots, perched on kitchen windows, scattered around the world and far removed from where the species evolved.  Perhaps because of artificial propagation and other such gardening techniques, the critical status of endangered plants seems to be lower on the conservation agenda.  But relying on horticultural specimens to resurrect or restore native plant communities is a dangerous gamble since such specimens may be maladapted, genetically impure and carry diseases novel to the environment. Recently, it has been highlighted that cacti in general are perhaps the most endangered of all biotic groups, not only due to plant collection, but from habitat destruction and imminent climate change.  Though cacti are certainly not cuddly, they are a unique biota supremely adapted to living in particularly harsh environments, and given our own pressing need to cope with increased global temperatures, perhaps there are things we can learn from this plant group if only we can ensure that they have sufficient space and protection to allow them to thrive.

Taiwan’s endemic salamanders (Hynobius sp.)

Hynobius glacialis. Photo by 游崇瑋, courtesy of http://eol.taibif.tw/pages/72138#3

Status – Unknown

In a slight departure from my usual approach of selecting individual species, here I consider the plight of the species complex of native salamanders in Taiwan’s mountainous highlands. And far from being ugly or scary, they are rather cute. However, the very limited ranges of these amphibians makes them particularly vulnerable to extinction, with disease, climate change and habitat degradation for agriculture or tourism development all significantly impacting all species. While, currently, only three species are listed officially in the IUCN’s Red List of Threatened Species (H. arisanensis, H. formosanus and H. sonani), Taiwan recognises another two only described in 2008 (H. fuca and H. glacialis). The last IUCN assessment of Asian salamanders seems to have taken place in 2004, so a more up-to-date one is certainly long overdue. Therein lies a significant problem with the IUCN system, since absence from the official Red List could embolden developers, politicians or other unscrupulous individuals to ignore conservation concerns about a non-listed species even if all evidence points to that species being under threat. Furthermore, it highlights the importance of researchers notifying the IUCN when they describe new species, especially if they deem them to be endangered, since it places an onus on the IUCN to organize a species assessment as soon as possible. In the meantime, considerable effort is needed in gathering even very basic ecological data on the five described species since an accurate IUCN assessment is dependent on the availability of verified data.

Desertas Wolf Spider (Hogna ingens – Blackwall 1857)

Deserta’s wolf spider. Photo courtesy of Emanuele Biggi, http://www.anura.it/emanuele/.

Status: Critically Endangered

With arachnophobia being one of the commonest fears globally, it is exceedingly difficult to promote conservation efforts for endangered spiders.  “Good riddance!” might be a typical response to news that a spider species is in danger of extinction.  One of the largest species of wolf spider in the world, with a body length of up to 40 mm and a leg span of 120 mm, the Desertas Wolf Spider is also one of the most endangered.  It is restricted to a single valley on the island of Desertas that forms part of the Madeira archipelago in the Atlantic Ocean.  This valley, the Vale de Castanheira, has become invaded by a non-indigenous grass Phalaris aquatica that completely outcompetes the native flora.  Where this invasive species occurs, the spider does not.  As a result, the distribution of this native top predator has diminished by almost three-quarters, with approximately 4,000 adults remaining.  Efforts to secure the future of this large spider have focussed on eradicating Phalaris aquatica through herbicides and fire and thereby recovering the native flora.  While this invasive plant has been shown to have a profound negative effect on the spider, an invasive millipede Ommatoiulus moreleti has become an important component of the spider’s diet, reinforcing the complexity of the invasive species issue.  Since this wolf spider shows some degree of opportunism in terms of diet – it has also been known to prey on juvenile lizards – there is hope that it could adapt to restoration of its’ habitat.  Conservationists have also recommended establishing an ex situ breeding programme to secure the future of the species, since restriction to a single valley renders it susceptible to catastrophic events.  While the appearance of the eight long striped legs and hairy abdomen of this spider might send shivers down the spine of many people, the disappearance of this species entirely from Desertas would be all the more ‘bone-chilling’ as it would mean yet another failure by humans to protect a unique component of an island’s fauna.

Hairy marron (Cherax tenuimanus – Smith 1912)

Hairy Marron. Image courtesy of Rodney Duffy.

Status: Critically Endangered

It is not often that the term ‘hairy’ could be ascribed to a crustacean, but this species of freshwater crayfish does indeed have a hirsute appearance with hair-like bristles over its carapace and other body parts.  It is endemic to the Margaret River in the south-western corner of Australia, where it is restricted to an area of occupancy of less than 10 km², which partly explains its critical status.  Hybridisation with the closely related, but introduced, Smooth marron (Cherax cainii) has been identified as the greatest threat to the species – one of the largest types of freshwater crayfish in the world (attaining weights of up to 2 kg).  The Smooth marron was introduced into the Margaret River in the 1980s, after which population declines in the Hairy marron began to be noticed.  Now, the introduced species occurs at all the sites where the Hairy marron occurs.  Given that the Hairy marron seems to prefer undisturbed habitat and the Smooth marron may have a slight competitive advantage where they co-occur, and the ever-increasing proportion of hybrid individuals that are being captured, the concern is that ultimately the Hairy marron will disappear as a genetically distinct species.  Illegal fishing is another issue threatening the species, but perhaps it is somewhat easier to control through public education than the over-riding issue of hybridisation.  Predation by introduced Redfin Perch, intensifying human-induced habitat degradation and competition with another crayfish species (Cherax albidus) are compounding the multi-faceted threats faced by the Hairy marron.  It is difficult to envisage how the genetic integrity of the Hairy marron can be maintained long-term without a considerable effort to eradicate invasive species from the Margaret River – control measures that could greatly alter the biology of the river given that many such species have become integrated into its food web.  The plight of the Hairy marron highlights the difficulty in dealing with introduced species once they have gained a foothold in a habitat.