Little monkeys need lots of space

This charming little creature is a White headed marmoset or "Sagui" (Callithrix geoffroyi). Tolerant of humans, they are often seen by tourists and will readily take pieces of fruit in their little hands. Classified as Least Concern (LC) on the IUCN Red List and in appendix II of CITES, surely conservation is no problem? Well, more or less.

Historically many were taken from the wild as pets, their very tolerance of man acting against them. This is tightly controlled these days, but their numbers are still decreasing. In the 21st century loss of habitat is the major problem, or more specifically, fragmentation of habitat. You might think that 20 forests of 1 km sq.would hold the same number of monkeys as 1 of 20 km sq. Indeed, given that predators tend to require much larger ranges and so are less likely to occur in small pockets, you might assume there would be more monkeys. You would be wrong (Chiarello & de Melo, 2001). There are various reasons.

a) Long term of course, small populations lack enough genetic diversity to stay healthy, but there are more immediate reasons.

b) Small forest fragments tend to favour trees and shrubs which are forest edge species, with proportionally less canopy or forest interior species (Cardoso da Silva and Tabarelli, 2000). Unfortunately, these are the very ones that produce the most fruit. Thus small monkeys, which tend to need a lot of fruit, suffer accordingly. In the same way, large fruit eating birds like macaws and toucans tend to be absent from isolated forests less than 250 hectares (Willis 1979).

Our little saguis are quite adaptable, and eat a lot of tree gum and insects (and anything really), so suffer less than fruit eating specialists, but it still cuts down their options. And they have another problem.

c). Small fragments may have fewer large fragments, but they still have plenty of cats, either native or feral from surrounding farm and residential land. Saguis and other small monkeys are especially susceptible to cats. They do their best, mobbing them and screeching, but that's not always enough. As an aside, it has been shown that being part of a "mob" actually reduces rather than increases monkey stress - it is tempting to extrapolate that to humans!

Driving through a landscape of fields and copses may appear more "natural" than a prairie of wheat or sugar cane, and it is, but maybe not that much more.

References
Cardoso da Silva JM, & Tabarelli M (2000). Tree species impoverishment and the future flora of the Atlantic forest of northeast Brazil. Nature, 404 (6773), 72-4 PMID: 10716443
Chiarello, A.G., de Melo, F.R. (2001). Primate population densities and sizes in Atlantic forest remnants of northern Espirito Santo, Brazil. International Journal of Primatology, 22, 379-396.

Willis, E.O. (1979). The composition of avian communities in remanescent woodlots in southern Brazil. Papéis Avulsos de Zoologia, São Paulo, 33, 1-25. 

In pursuit of a fox

"The English country gentleman galloping after a fox - the unspeakable in full pursuit of the uneatable."- Oscar Wilde in A Woman of No Importance.

An overcast Boxing Day in a quintessentially English village/town in South Gloucestershire. The place is typically peaceful, although not so that morning. In fact, it looked like a scene from John Constable’s paintings: an excited throng at the village centre; huntsmen and women on their powerful hunters and invigorated hounds prancing at the sound of the bugle; the bystanders cheering wildly with much fervour- setting off towards the rolling countryside is a typical fox hunt.

The fox hunt might sound strange to the non-British. It is commonly viewed as a traditional English sport, integral to a country life, complete with high expenses and pomp. Packs of trained hounds pick up the scent of the red fox (Vulpes vulpes) and chases it across the countryside (there being no geographical limitations), followed by riders on hunters. One can easily picture the damage caused by the galloping of horses on fences and hedges on the way and agricultural fields.

However, since fox hunting is technically banned in the UK via the Hunting Act 2004 (enforced since February 2005, much to the dismay of the supporters), the hounds now supposedly follow the trail of an artificial scent (an errant fox in their path is considered as an accident). Anti-hunt groups still maintain that fox hunting is rife- after all, no one can keep up with the chase (unless they masquerade as huntsmen) and some have boasted along the lines of getting around the law.

Hunt supporters view fox hunting (or any other seasonal hunting) as neither cruel nor wrong. The supporting arguments are many: an important rural English tradition, conservation, and purging nature by eliminating diseased/old/injured/young foxes. A study, which sits on the fence, states that in the event of a fox-hunting ban, there would be no detectable population increase as the number of foxes killed by hunting is relatively small. Furthermore, foxes (which are considered vermin- along with squirrels and rats) haven’t exactly been making themselves endearing- for instance, they indulge in an incomprehensible carnage in hen coops even though all they need is only one hen. As a control measure, hunting is presented as a humane option (when compared to poisoning/shooting/snaring- which entails greater suffering, with other animals as inopportune victims) - whilst the chase itself is said to take just under an hour, foxes are killed (supposedly instantaneously) after a chase averaging 17 minutes.

Opponents of the hunt (a list which includes luminaries such as Thomas More, Oliver Cromwell, and Dr Samuel Johnson) finds it nonsensical, cruel, and unnecessary- a sport which transforms the huntsmen into beasts, sans any semblance of human virtues. Fox-hunting has no significant reduction in the fox population and doesn’t provide any sustenance. The only gain (and for those so inclined) is obtaining pleasure from witnessing such unnecessary suffering. One criticism is that the sport is limited to and glorifies the lifestyle of the rarefied strata of society and supporters of a certain political party (admittedly, a glance at my acquaintances who keep hounds supports that statement).

So here it is- an exclusive sport, a mixture of violence and sentimentality for olden traditions, transporting one back into feudal times. Any thoughts?

References/Sources:
Newall, V. (1983). The Unspeakable in Pursuit of the Uneatable: Some Comments on Fox-Hunting Folklore, 94 (1), 86-90 DOI: 10.1080/0015587X.1983.9716259

FRANKLIN, A. (1996). On Fox-hunting and Angling: Norbert Elias and the 'Sportisation' Process Journal of Historical Sociology, 9 (4), 432-456 DOI: 10.1111/j.1467-6443.1996.tb00106.x

Gunn, A. (2001). ENVIRONMENTAL ETHICS AND TROPHY HUNTING Ethics & the Environment, 6 (1), 68-95 DOI: 10.2979/ETE.2001.6.1.68

Baker PJ, Harris S, & Webbon CC (2002). Effect of British hunting ban on fox numbers. Nature, 419 (6902) PMID: 12214224

Baker, PJ., Harris, S., Webbon, CC (2002). Response to Aebischer, NJ, Baker, SE, Johnson, PJ, Macdonald, DW, and Reynolds, JC. Nature, 423, pg. 400

Anderson, A. (2006). Spinning the Rural Agenda: The Countryside Alliance, Fox Hunting and Social Policy Social Policy and Administration, 40 (6), 722-738 DOI: 10.1111/j.1467-9515.2006.00529.x

http://www.telegraph.co.uk/earth/countryside/8872182/Why-fox-hunting-is-more-popular-than-ever.html
http://www.telegraph.co.uk/earth/wildlife/8977417/David-Cameron-to-ditch-foxhunting-U-turn.html
http://www.guardian.co.uk/uk/2011/dec/26/fox-hunting-ban-call-repeal

Marine mammals and their future

Marine mammals have borne the brunt of mankind’s unsustainable overexploitation, resulting in population decline and species extinction. Hunting for fur, blubber, and meat in the 19th and 20th centuries resulted in the extinction of three species – the Caribbean monk seal (Monachus tropicalis), Atlantic gray whale (Eschrichtius robustus), and the Steller’s sea cow (Hydrodamalis gigas). The most recent extinction, due to its use in traditional medicine, was that of the Baiji (Lipotes vexillifer) in 2008, a dolphin endemic to the Yangtze River.

In this backdrop, the August 16th edition of PNAS featured an excellent research (it truly is wonderful to come across such), entitled ‘Global distribution and conservation of marine mammals’, by Sandra Pompa and Gerardo Ceballos (National Autonomous University of Mexico) and Paul Ehrlich (Stanford). The mammalian species considered in the study were 129 in total (123 marine and 6 freshwater species), grouped into the orders of Cetacea, Sirenia, and Carnivora (common examples being whales, dolphins, porpoises, otters, seals, and polar bears) .

Method
The researchers created geographic range maps for the 129 species and the map of the water bodies were split into grids of roughly 10,000 km2. They determined the number of species in each grid cell and calculated the total number of cells occupied by each species. Breeding, calving, and feeding grounds, and migratory routes were also factored in. The result was a composite global distribution map of water bodies, revealing locations of ‘global species richness, irreplaceable sites, endemism, and threatened species.'

Results
1. All species can be represented in 20 global key conservation sites that cover at least 10% of the species' geographic range. These sites were determined on the basis: number of species present (species richness), severity of the risk of extinction for each species, and whether the species was endemic to the area.

2. Preserving 9 of such sites (mostly in temperate latitudes located off the coasts of Baja California in Mexico, the Atlantic coast of North America, Peru, Argentina, north-western Africa, South Africa, Japan, Australia, and New Zealand) would protect the habitat of 83.72% (108/129) of marine mammal species (including 5 endemic species) since these have high species richness.

3. The remaining 11 sites (6 freshwater, 5 marine: areas around Hawaiian and Galapagos Islands, Kerguelen Islands in the southern Indian Ocean, San Felix and Juan Fernandez Islands off the coast of Chile, Mediterranean Sea, Lake Baikal in Siberia, Caspian Sea, and major rivers such as the Amazon, Ganges, Indus, and Yang-tze) were tagged ‘irreplaceable key conservation sites’ of great conservation value due to the presence of endemic species, which, consequently, face a greater risk of extinction.
Eg. Galapagos fur seal (A. galapagoensis) and the Mediterranean monk seal (Monachus monachus).

4. Strong correlation of marine mammal species richness with human impacts (Spearman rank correlation (rs = 0.693, n = 46,164, P < 0.01 for climate disruption; rs = 0.666, n = 46,164, P < 0.01 for pollution; and rs =0.678, n = 46,164, P < 0.01 for shipping). The existing deterioration of the marine ecosystems due to anthropogenic activities (and the potential for more deterioration not just at these sites but also elsewhere) was evidenced by around 70% percent of most impacted areas being within or near key conservation areas. Factoring in other impacts such as commercial fishing would result in stronger correlation (and perhaps also global climate change, habitat degradation, ocean acidification, exploitation of natural resources such as oil and gas, hunting, tourism, and plastics?)

5. 10% of all marine mammals were considered to be vulnerable, 11% endangered, and 3% critically endangered. The following vulnerable species were identified:

i. Vaquita (a porpoise species), endemic to the Gulf of Baja California, has the most restricted range. Its population has been declining rapidly and there are only 150-300 individuals in the wild (1/5 of the population are killed in gillnets each year).

ii. Sea lions such as the endemic Australian sea lion (Neophoca cinerea) and the Galapagos sea lion (Zalophus wollebaeki), and the restricted range New Zealand sea lion (Phocarctos hookeri).

iii. Seals such as the freshwater and endemic Baikal seal (Pusa sibirica), and the endemic Galapagos fur seal (Arctocephalus galapagoensis) and Hawaiian monk seal (Monachus schauinslandi).

iv. Whales at the brink of extinction, such as North Atlantic right whale (Eubalaena glacialis) and Sei whale (Balaenoptera borealis), due to overharvesting, pollution, bycatch, and exhaustion of prey-species populations.

v. Dolphins such as the endemic New Zealand dolphin (Cephalorhynchus hectori) and the restricted range Australian Snubfin dolphin (Orcaella heinsohni).

Implications
This research could be a useful tool for environmental organisations and governments in identifying conservation areas and anthropogenic threats so as to protect endangered marine mammals and keep the oceans’ ecosystem functional. Mammals hold a lofty position in the food chain- consequently, their population dynamics would affect all other components of an ecosystem (and in human communities, by extension).


Pompa S, Ehrlich PR, & Ceballos G (2011). Global distribution and conservation of marine mammals. Proceedings of the National Academy of Sciences of the United States of America, 108 (33), 13600-5 PMID: 21808012



And the must read: http://www.pnas.org/content/suppl/2011/07/27/1101525108.DCSupplemental/sapp.pdf


Image source: Apollo 17

Mr Wolf, I presume?

Yes, appalling as it sounds, I read the Trinity edition of my alumni magazine only now. One of the stories (pg 13) caught my eye for various reasons.

Those of us who have a long-standing interest in Egyptian mythology would recall Anubis, the jackal-headed god of the dead, who held the unappealing portfolio of funerals, afterlife, mummification, fate of souls, and protection of the dead and their tombs. This was presumably because Anubis’ animal counterpart, the Egyptian Jackal (Canis aureus lupaster; Hemprich and Ehrenberg, 1833), preferred to occupy burial grounds. C.a.lupaster was considered to be a large, rare subspecies of the golden jackal (Canis aureus; Linn. 1758) even though there has been a historic (ahem) bone of contention over whether it is a jackal or a wolf (given its wolf-like morphology). Ancient Greeks considered these to be smaller versions of the European wolves; evolutionary biologist Thomas Huxley, after comparing the skulls of C.a. lupaster and Indian wolves, considered the species as grey wolf; Walter Ferguson (1981) argued that it was a species of wolf after studying its cranial measurements.

But research published earlier this year by collaborators from Oxford University's Wildlife Conservation Research Unit (WildCRU), University of Oslo, and Addis Ababa University has established the Egyptian jackal’s true skin. When the mitochondrial DNA of the Egyptian jackal was compared with that of the golden jackal, wolves, and wolf-like canids, the results demonstrated that the Egyptian jackal (whether in Egypt or Ethiopia) is (and should be renamed as) an African Wolf, a subspecies of grey wolf or a separate species in itself, which existed alongside the golden jackals and the rare Ethiopian wolf (Canis simensis, an unique but endangered species). Furthermore, sequencing of mtDNA from Ethiopian highland golden jackals revealed that these were, in fact, Egyptian jackals (i.e. the African Wolf). African wolves are closely related to the Indian (Canis lupus pallipes) and Himalayan wolves (Canis lupus chanco- with 2.4% divergence).

What does this bode for the species? The authors of the PLoS study called for assessing the status of the African wolf. Its previous classification as a subspecies of golden jackals meant being listed as a species of least concern by the IUCN. But since this is now the only grey wolf species in Africa, this could be rare and endangered.

References:

Rueness EK, Asmyhr MG, Sillero-Zubiri C, Macdonald DW, Bekele A, Atickem A, & Stenseth NC (2011). The cryptic African wolf: Canis aureus lupaster is not a golden jackal and is not endemic to Egypt. PloS one, 6 (1) PMID: 21298107

Oxford University's Press Office

WildCRU

Image: Golden jackal by Stig Nygaard