Tag Archives: Morgan E. Heim

CAT in WATER Kickstarter Launch!

Support the Kickstarter project to document them in the wild  here.

The fishing cat is up and running! We have 90 days to raise the first round of funds for the CAT in WATER expedition. Check out our Kickstarter project and watch the short video. You can also learn about all the paybacks in store for our supporters. Who wouldn’t want a care package from Thailand and the knowledge they are helping a gorgeous, wild animal in need?



Gangster Birds of the Kalahari Desert

A drongo in the Kalahari. (Photo/Andy Radford, University of Bristol)

Drongos, African Kalahari Desert birds with a penchant for thievery, are taking a turn towards the avian equivalent of organized crime, a new study finds.

The victims in this case, pied babblers, have long contended with the risk of drongos popping in to make off with the babblers’ hard-earned insect prey. Now it seems a set of behaviors have evolved that are taking this interaction from a purely parasitic relationship to one of more mutual benefit. Researchers found that the drongos form protection squads for foraging babblers, keeping an eye out for trouble and strong-arming danger when it arrives.

“Like any good gangster,” says Andrew Radford, a scientist with the University of Bristol who led the research team, “as well as lying and stealing, the drongos also provide protection by mobbing aerial predators and giving true alarm calls on some occasions.”

That means pied babblers can spend less time watching for predators and more time looking for prey. The relationship is not without its caveats. Drongos still aim to take advantage of babblers, crying wolf to scare the babblers and grab the insects. The babblers likely put up with it, the researchers say, because the benefit of not having to worry about predators outweighs the cost of the drongos’ antics.

The research, which is a collaboration with the Universities of Bristol, Cambridge and Cape Town, is published online in the current issue of Evolution.

Andy Radford (University of Bristol) and a pied babbler in the Kalahari. (Photo/Matthew Bell, University of Cambridge)

A pied babbler in the Kalahari. (Photo/Andy Radford, University of Bristol)


Quick Hit: Desert bats, staving-off dehydration by the skin of their wings

The researchers found total water loss in the desert-living Pipistrellus kuhli was just 80 percent of other nondesert species. (Photo/Sahi Pilosof)

Desert-dwelling bats lose water at a slower rate than non-desert bats, a new study finds. And their secret appears to be skin deep. Researchers from the Ben-Gurion University in Israel looked at the desert bat Pipistrellus kuhli, and found that the amount of fat in the skin helped stem water loss. Animals typically lose water through evaporation from the skin or from the mouth and nose when breathing. This finding helps explain how an animal with bare wings that expends so much energy in flight can survive in such an arid environment. Researchers, lead by Dr. Muñoz-Garcia plan to look at eight other species of desert bat to see if the same holds true for them.


Cane toads heart climate change

Cane Toad, AKA Bufo marinus, AKA troublemaker extraordinaire (Photo/ Eli Greenbaum)

Cane toads like it hot, and with climate change poised to raise temps in Australia, this persistent, invasive species could soon be living it up even more.

At least that’s the word coming out of new research from the University of Sydney and presented at the Society for Experimental Biology’s annual conference in Prague.

A lot of what we hear about climate change focuses on habitat loss (cue rising sea levels) or species extinction (sorry red wolf and coral reefs), but here’s another way the pesky, poisonous cane toad can flip the amphibian bird to mankind – warmer climes mean prolific times as far as the toad is concerned.

“The negative effect of high temperature does not operate in cane toads, meaning that toads will do very well with human induced global warming,” said Professor Frank Seebacher from the University of Sydney in a press release.

Many of you reading this are probably familiar with the story of the cane toad, but here’s the quick shake down. In the mid 1930s, Australian biologists, hoping to stem the onslaught of beetles ravaging cane fields, introduced cane toads to Queensland and the Northern Territory. Unfortunately, toads passed on the beetles, instead turning their appetites towards lizards, snakes and other native wildlife. To compound factors, the toads secrete a toxic substance that can do a serious number on just about anything that tries to eat it. So the cane fields now have beetles and bucket loads of poisonous toads. Sigh.

And because of research by Seebacher, we now have a good idea that toads are going to thrive even more as temperatures rise from climate change. Warmer weather makes for stronger, or at least more efficient, heart and lungs in the cane toad, Seebacher found. And if that’s not unsettling enough, the study also states “the cane toad can adapt its physiology in response to a changing environment repeatedly and completely reversibly many times during its lifetime.”

Will nothing temper their proliferation?

Before you totally throw up your hands and say, “Why do I read this if all you’re going to tell me is bad news,” here’s a ray, or sliver, of hope. Maybe, just maybe, this phenomenon will prove true for other toads, ones we actually would like to see stick around. I’ll get back to you when Seebacher conducts that study.


Changing Chesapeake Bay acidity endangers oysters

New research shows that the shell growth of Crassostrea virginica from Chesapeake Bay could be compromised by current levels of acidity in some Bay waters. (Photo/Chris Kelly, UMCES Horn Point Laboratory)

Growing up at the mouth of the Lynnhaven River in Virginia, where the river meets the Chesapeake Bay and the bay meets the ocean, I can’t tell you how many mornings I woke up and looked out my window to see neighbors wading in rubber boots, harvesting oysters from the beds just off our riverbank. For some, like my neighbors, oysters were a way to connect with the land and make a little extra dough. For others it was their livelihood. The act was something that just was. It never occurred to me that the oysters could one day be gone.

That’s why I was especially alarmed to read this new report from the University of Maryland Center for Environmental Sciences. Rising acidity levels in the Chesapeake Bay are making it harder for oysters to grow their shells. I’ve heard the news before that rising ocean acidity from sources such as carbon dioxide can spell disaster for marine wildlife, but this new study shows that acidity is rising faster in the Chesapeake Bay than in the ocean and having a measurable impact on Bay wildlife.

“With oyster populations already at historically low levels, increasingly acidic waters are yet another stressor limiting the recovery of the Bay’s oyster populations,” said marine biologist Dr. Roger Newell of the UMCES Horn Point Laboratory in a press release.

But don’t turn around to blame climate change just yet. The story is a bit more nuanced than that, though the source of the problem still has to do with us. In the saltier areas of the bay, the acidity is going up, leading to thin shell growth that makes oysters more vulnerable to predators, including crabs. But in more freshwater portions of the Bay, acidity is actually going down, said the study, which looked at more than 20 years of historical water quality data from the Bay.

The difference seems to be not atmospheric carbon dioxide, but the base of the food chain. In freshwater areas along the upper Chesapeake, sewage and agricultural runoff cause phytoplankton blooms, which consume carbon dioxide and lower acidity, said the study. Sounds good at this point right? Here’s the catch. As phytoplankton drift through the Bay, they are eaten by animals and other bacteria, releasing the carbon dioxide that the plankton so diligently consumed in the first place. This carbon dioxide lingers in the water, leading to spikes in acidity in the saltier regions of the Bay near the ocean.

“While these variations in acidity may improve conditions for shellfish in some areas, they may also magnify detrimental impacts in others,” said lead author Dr. George Waldbusser of Oregon State University in a press release. “What our study indicates is there may be an important shifting baseline and without better measurements we will fail to fully understand impacts on estuarine biota.”

Beyond the science itself, this study highlights how connected and varied our environment is. It lays out a pathway of human-induced consequences to an ecosystem, and teaches that we need to look beyond one-to-one cause and effect. Erin Voigt, an undergraduate student who worked on the study puts it well. “The complex response of oyster shell formation to temperature, salinity, and acidity highlights the need to understand how the entire ecosystem is changing, not just acidity,” she said.

And that ecosystem includes us.

You can view the article online in the journal Estuaries and Coasts.


Red squirrels are people too. They adopt

Red squirrel taking an adopted baby from nest. (Photo/Ryan W. Taylor)

In another life, I must’ve been a dog. Whenever I’m out walking and see a squirrel, I have an almost uncontrollable urge to see how close I can get to it before the scrappy rodent scrabbles up a tree. Inevitably, a staring contest ensues, which the squirrel usually ends up winning.

My suppressed animal urges aside, I do notice something kind of educational about squirrels. They tend to be alone. When they’re not, they are usually chasing each other like crazed maniacs in a not too friendly manner without regard to life or other happenings.

That’s why it might come as a surprise that they practice a typically human behavior – they adopt. And they adopt outside their social group. A new study by researchers at the University of Alberta determined that red squirrels will take in abandoned or otherwise parent-less young and raise them as their own, a seemingly altruistic act. The behavior turns out not to be as charitable as it sounds – the squirrels do get a survival perk. But the discovery is nonetheless an unusual one in the animal kingdom, with its own squirrely flare to boot.

Jamieson Gorrell, a Ph.D. student in evolutionary biology at the University of Alberta and lead of the study, was observing a population of Yukon red squirrels and noticed a lone female had taken a baby from an abandoned nest to raise as her own. When Gorrell sifted through 20 years of red squirrel research from the area, he found four other instances of the same behavior. Not only that, but in each account, the baby adopted was a relative.

Gorrell found that despite their antisocial tendencies, red squirrels are still able to recognize, and decide to care for, relatives. Right now the predominant notion is that the chitter-chatter squirrels screech out to mark territory or ward off others contains vocal clues about relativity. So an encroaching squirrel could hear the calls of another adult, and recognize kinship. If that other mother disappears, the encroaching squirrel may recognize the kinship of the abandoned nest and take action.

In addition to the novelty factor of the behavior, the study authors also state that this finding proves a long-standing evolutionary theory true. It is a concept known as Hamilton’s Rule, which suggests that despite “the law of the jungle and survival of the fittest,” animals can be altruistic.

Though for red squirrels, it’s a tempered altruism. The red squirrel is still helping out a member of its bloodline, and will only help one baby out of a litter. Adopting more than one is “out of the question,” according to the study, as the strain of adding more than one baby to a single mother’s already full house would outweigh any benefits.

You can read more about the study in the online journal Nature Communications, or visit this link http://www.redsquirrel.ca/KRSP/Media.html to get more info, cute pics, and free copy of the study.


Surfing crocodiles take to the high seas

A 4.8 m male estuarine crocodile ready for release with satellite transmitter. This crocodile traveled over 590 km by sea. (Courtesy/University of Queensland)

Next time you’re out sailing the high seas and think you’ve spotted a crocodile hanging ten, no need to get your eyes checked just yet. Turns out crocs do surf ocean currents, albeit sans boards and all the crazy wipeouts.

The behavior tracked by researchers out of Queensland, Australia, helps explain why the reptiles are so widespread, yet genetically similar.

Estuarine crocodiles which typically live in saltwater habitats like rivers and mangroves occupy a range covering about 10,000 km2 stretching from East India to Fiji and southern China to northern Australia, said the study. Geographic isolation tends to support the evolution of different species. But despite living in places separated by thousands of miles of open ocean, a crocodile living in Fiji is likely the same kind of croc living in Australia.

“The estuarine crocodile occurs as island populations throughout the Indian and Pacific Oceans, and because they are the only species of salt-water living crocodile to exist across this vast area, regular mixing between the island populations probably occurs,” said Hamish Campbell with the University of Queensland, and study lead in a press release.

But until now, scientists weren’t sure how. Stories have floated in over the years of ocean-bound crocodiles, even though the toothy predators are no Mark Spitz when it comes to swimming. Campbell and his colleagues from Queensland Parks and Wildlife Service and Australia Zoo set out to monitor the mobile capacity of crocs. They used acoustic and satellite tracking to follow the movements of 27 adult crocodiles over the course of a year. The crocodiles revealed an astonishing range of movement, regularly traveling 50 kilometers or more from their stomping grounds to the mouth of the river and out into the sea.

Croc’s, it seems, like to “go with the flow,” according to the researchers. Tides and currents dictate the timing and extent of a crocodile’s swim, with crocs typically beginning a swim within an hour of a changing tide, following the movement of the water, and returning to shore when water is no longer headed in the desired direction. Similar behavior applies to swims in the open ocean, where crocs ride the currents.

One croc, a roughly 15-foot- long male, traveled more than 400 kilometers in 20 days from the east coast of Cape York Peninsula through the Torres Straits to the west coast of Cape York, according to the study. At one point, the croc stopped on the shore of the Torres Straits and stayed there for four days waiting for more ideal currents.

Campbell explains that this type of behavior, “not only helps to explains how estuarine crocodiles move between oceanic islands, but also contributes to the theory that crocodilians have crossed major marine barriers during their evolutionary past.”

The full paper is available in the British Ecological Society’s Journal of Animal Ecology.


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