Birds / Herps / Mammals / Science & Research

Great tits, yellow-bellied marmots, and other not-entirely-awful news about climate change

wandering albatross colony by Vincent Lecomte

From the plight of polar bears (oh, dear polar bears) to yet another mosquito-borne illness (fuck mosquitoes)… there’s a lot of evidence to support that feeling of gloom and doom surrounding the effects of climate change. So I started collecting examples of animals that appear to be taking advantage of — or at least adjusting to — climate change, however short-lived the benefits may be.

There are, to my surprise, quite a few studies on vertebrate species moving or expanding to higher latitudes and altitudes (like the trumpeter swan), enjoying milder cold seasons (go white-tailed deer) along with warmer waters (yay, grey nurse shark), and displaying awesome feats of flexibility. Here are some of my favorites.

yellow-bellied marmot pup by Raquel MonclusYellow-bellied Marmot (Marmota flaviventis)

In the Rocky Mountains, yellow-bellied marmot numbers have tripled in 10 years, and the boom’s been linked to the increasing size of their bellies. An Imperial College London team examined a 1976–2008 dataset and found that the rodents grew from an average of 3.1 kilograms in the first half of the study, to 3.4 kilograms in the second half.

Turns out, climate-driven changes in their hibernation patterns gave them longer to grow. With more warm days each year, earlier emergence from hibernation and earlier weaning of young led to a longer growing season and larger body masses before hibernation. The biggest effect came from improved survival among older marmots during wintertime, thanks to a hardiness driven partially by body size. [Nature via Nature News]

Great Tit (Parus major)

(YES FINALLY, a story about great tits and climate change that doesn’t involve how global warming means more bikinis.) Many songbirds time their breeding with the peak emergence of resources so that there’ll be plenty of food available for their newborns. As the climate warms, both predator and prey species have advanced their spring schedules, but some tits have failed to keep pace with caterpillars. Being out of sync means they’re breeding 2 weeks too late, and there’s not as much food left for hungry babies.

Netherlands Institute of Ecology researchers spent over 40 years tracking a great tit population: when they lay their eggs, how many eggs hatch, and how many hatchlings survive to reproduce. They found that, even with this loss, the number of great tits in the population has remained fairly stable. With fewer young birds, there’s less competition, and more of them make it through the winter. [Science via ScienceNOW]

wandering albatross taking off by Nicolas GascoWandering Albatross (Diomedea exulans)

Warming has led to increased average wind speeds over the southwestern Indian Ocean — which has helped albatrosses gain weight and bred more successfully, a team from Centre d’Etudes Biologiques de Chizé in France found. Specifically, higher wind speeds mean shorter foraging trips during their nesting season (when males and females take turns incubating eggs and tending to chicks): 9.7 days in 2008, compared with 12.4 days in 1970.

Shorter shifts on the nest resulted in fewer abandoned eggs and chicks: 66% of eggs laid in 1970 resulted in live chicks, compared with 77% in 2008. Albatrosses also began to fatten up, weighing on average 1 kilogram more now than they did 20 years ago (that’s up to a 12% increase in body mass). [Science via ScienceNow]

Three-lined Skink (Bassiana duperreyi)

Previous work has shown that the temperature of a nest (usually under sunny rocks and logs) can affect a hatchling’s size, speed, and sex. Herpetologists from University of Sydney found that between 1997 and 2006, the lizards’ nest temperatures increased by about 1.5°C.

They also collected wild females, and when the babies hatched, each lizard was placed in a 24°C cage with two hiding places: overturned plastic flower-pot trays with entry holes cut in the sides… except one was a decoy with Plexiglas covering the opening. Over a 4-day experiment, warm-incubated lizards made on average one or two more escapes (found the real hiding place under 30 seconds) during the second 2 days than they had during the first 2 days. Cool-incubated lizards showed no such gains. The findings suggest that lizards incubated in warmer environments may learn faster than others, giving some a cognitive edge and helping them escape predators. [Biology Letters via ScienceNOW]

coring a Porites coral by Timothy Fraser CooperAt Least One Coral (genus Porites)

(Okay, not a vertebrate, but… Yes! A coral!! I’ll take it! After all, there are just so many stories about corals bleaching themselves.) Work by biologists from the Australian Institute of Marine Science suggests that in some cooler regions, climate change has led to the faster growth of some corals — and that growth may compensate for some negative effects, so that technically, it’s a net gain for the reefs.

The team looked at tree ring-like growth bands in a particularly long-lived coral in the Indian Ocean off western Australia, matching annual growth from 1900 to 2010 with known sea surface temperatures. They found that at the southernmost — and coolest — reef, there was a 23% increase in growth rate since 1900. Two other southern sites had increases of about 9% and 5%. The temperature is typically cool enough in those regions to limit coral growth rates, so warming has apparently been helpful. [Science via ScienceNOW]

Glass Sponges (class Hexactinellida)

(Also not a vertebrate, but this just made headlines this month.) These sponges with silica skeletons grow incredibly slowly, sometimes locked in arrested growth for decades. But when the Larsen A ice shelf collapsed in 1995, it let in sunlight, prompting a phytoplankton boom. The colony of glass sponges underneath the ice shelf responded to the feeding frenzy with a massive growth spurt. Researchers from Alfred-Wegener-Institut had visited the site in 2007, and when they revisited four years later, the sponges had doubled in biomass and tripled in abundance. [Current Biology via New Scientist, ScienceNOW]

killer whales in the Arctic by Steven FergusonKiller Whale (Orcinus orca)

Melting ice is turning the Arctic Sea into a giant buffet for killer whales. They’ve been arriving in growing numbers to feed on seals (ringed, harp, bearded, and hooded) and whales (narwhals, belugas and bowheads), according to scientists from the University of Manitoba.

Warmer temperatures make it easier for the whales to hunt since their prey is less likely to climb onto sea ice or hide below it to escape. The researchers supplemented their scientific observations with information from over 100 interviews with hunters and elders from Canadian Nunavut Inuit communities. (‘Aarlirijuk’ is the fear of killer whales.) [Aquatic Biosystems via Climate Wire]

North American Beaver (Castor canadensis)

Finally, and this isn’t totally on topic but… did you know that beavers help sequester carbon? We know that these little engineers clear-cut trees and build dams to block streams. Now, a new study suggests that these dams and the sediments corralled behind them temporarily keep greenhouse gases out of the atmosphere. BUT, when the animals abandon these sites, the carbon leaks back out.

A fluvial geomorphologist from Colorado State University, Fort Collins, studied the wetlands and floodplains upstream of beaver dams (collectively called “beaver meadows”). Because the water table is elevated behind an intact beaver dam, oxygen can’t get to the organic matter buried there, so they decompose more slowly. Wood buried in soggy beaver meadows can last 600 years, but when the water table drops and the soils dry out, decomposition releases carbon dioxide to the atmosphere.

They found that, on average, 3.3% of the sediments in abandoned beaver meadows is carbon. Today, abandoned beaver meadows contain about 736,000 metric tons of stored carbon. But if all the beaver dams were occupied with their wetlands intact, beaver meadows would be storing about 23% of the landscape’s soil carbon — or around 2.7 million metric tons. [Geophysical Research Letters via ScienceNOW]

Wanna know help with climate warming? Eat some bugs, get used to jellyfish burgers.

Images provided by researchers (from top to bottom): Vincent Lecomte, Raquel Monclus, Nicolas Gasco, Timothy Fraser Cooper, Steven Ferguson, Ben Hulsey

yellow-bellied marmot pup by Ben Hulsey

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