Monday, December 14, 2009


Brian Hutchinson / IUCN
Leatherback sea turtles lay their eggs on beaches but warming sand can actually alter their gender balance, the IUCN says. Over time, the species could see "an increase in the number of females relative to males," threatening its population stability. "Increases in temperature have also been shown to lead to hatchling abnormalities and developmental and other health problems." Beach erosion and changing ocean currents are also obstacles. While leatherbacks have adapted to past climate shifts the current warming trend is "believed to be faster than anything leatherbacks and other marine turtle species have encountered previously," the IUCN says. Flagship for: Impacts of warming temperatures, rising sea levels and changing ocean currents

Staghorn corals are the collective name for some 160 species representing one-fifth of Earth’s reef-building corals, the IUCN says. These corals are very sensitive to higher sea temperatures, which can bleach and then kill coral, as well as to increased ocean acidity from higher CO2 levels. "‘Mass’ coral bleaching is a new phenomenon dating back to the 1980s," the IUCN says, "and is now the main cause of coral mortality and reef deterioration globally." A third of all coral species are already listed as threatened on the IUCN Red List. "Adaptation (for corals) is very slow and unlikely to be able to keep up with" with the warming trend, the IUCN adds. Flagship for: Impacts of rising sea temperatures and increasing ocean acidification

Many freshwater habitats of salmon are facing warmer temperaturess and altered seasonal flows, the IUCN says. "While human activities are largely responsible" for declines in many salmon populations, "climate change could now exacerbate or even supersede these threats, particularly in the southern part of their natural range." Adaptation for salmon is made harder by existing pollution and habitat pressures. Flagship for: Climate effects on freshwater ecosystems, and how impacts on wild species can have a direct effect on economies

"Belugas are increasingly at risk from vessel and industrial noise, ship strikes and toxin exposure," the IUCN says. "As Arctic ice cover rapidly declines and the passages across northern landmasses become more navigable, humans will gain easier access to formerly pristine areas that have long served as refuges for Belugas and other marine mammals." As for adapting, the IUCN notes belugas' "resilience has already been compromised by the historical reductions in population sizes and ranges." Flagship for: Indirect effects of climate worsening existing threats from people

Ringed seal reproduction is being disrupted by Arctic summer sea ice that is melting earlier each year, the IUCN says. "Both ice and snow must be stable enough in the spring season to successfully complete the six week period of lactation. If the landfast ice breaks up too soon, pups may be separated prematurely from their mothers, resulting in high pup mortality." Moreover, insufficient snow early in the breeding season as well as "spring rains or warm spring temperatures can cause the roofs of lairs to prematurely collapse, leaving ringed seals unsheltered and exposed to predators." As for adapting by moving, the IUCN says "their already high-latitude distribution range limits their potential for pole-ward migration." Flagship for: Impacts of reduced Arctic summer sea ice

Arctic foxes "face habitat loss, competition and predation from red foxes" as higher temperatures warm the tundra, the IUCN says. "The encroachment of red foxes into more northern areas has already been documented." Moreover, arctic foxes prey largely on lemmings and voles. "Milder and shorter winters are predicted to cause declines in the regularity of these rodents’ population cycles, as well as decreases in their overall numbers," the IUCN says. Because their habitat area is shrinking, the IUCN says, the number of arctic foxes "that can be supported worldwide is likely to decrease." Flagship for: Disruptive effects on the balance among species

Koalas' reliance on Eucalyptus leaves for food could mean mass malnutrition, the IUCN says, since increasing CO2, while allowing plants to grow faster, "also reduces protein levels and increases tannin levels in plants' leaves. As CO2 levels continue to rise, Koalas and other browsers will need to cope with increasingly nutrient-poor and tannin-rich Eucalyptus leaves." Global warming models also predict more wildfires and longer, more severe droughts in places like Australia. Koalas are vulnerable to both. Koalas do not have great potential for adapting, the IUCN says, "as changes are occuring faster than koalas are likely to have experienced in the past." Flagship for: Effects of elevated CO2 levels on plants and on the animals that rely on them for foo

Emperor penguins "are predicted to lose sea ice platforms for breeding and face changes in food availability," the IUCN states. Less sea ice could make it easier for penguins to reach water, but it also means growing chicks still without their waterproof feathers could drown by falling through thinner ice. As for food, less sea ice is projected to reduce krill, the shrimplike invertebrates that penguins rely on. Could Emperor penguins adapt by moving to dry land? Two colonies do live on land and have remained stable over 20 years, the IUCN says, so "potentially" that's doable if they find suitable food inland. Flagship for: Impacts of rising sea temperatures and melting sea ice

Tarik Tinazay / AFP-Getty Images
Polar bears get most of the attention when it comes to warming and endangered species, but they're not alone. Even clownfish are in danger, according to a report released Monday by the International Union for the Conservation of Nature, the largest association of species experts in the world. The 10 "flagship species" listed in the report are shown here. In the case of clownfish, aka the Nemos of the underwater world, their coral reef habitats are under severe threat from warmer waters that can bleach, and then kill, coral. Moreover, acidification of sea waters due to higher carbon dioxide levels prevents coral and some other skeletal-based organisms from forming shells. Flagship for: Impacts of coral reef degradation due to warming seas and increasing ocean acidification

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