Lost in Migration

European_Robin_2German scientists have found that radio waves can throw birds off their migration paths. The phenomenon is most acute in cities. The paper was published in Nature last week.

The scientists discovered the issue when trying to research the impacts of subtle magnetic fields on bird migration in their lab in Oldenburg, Germany, a BBC article reports. A much-replicated method of studying bird migration and magnetic fields didn’t work until the scientists shielded their experiment from radio waves of a certain frequency.

They study found that birds are adversely affected by EMF (electromagnetic frequency) radiation and levels much lower than humans are. So low, in fact, that the BBC article says only quantum level phenomena can explain it.

The research was conducted for seven years. In the BBC article, a scientist explained that the team wanted to be extra careful before reporting the unexpected findings, which they knew would be controversial.

Read the Nature article here. (Subscription or fee required for full article.)
BBC article here.
Article in The Australian, here.

Photo: European robin, the subject of the lab experiments. By Sunnyjim (Own work) [CC-BY-SA-2.0-uk (http://creativecommons.org/licenses/by-sa/2.0/uk/deed.en)%5D, via Wikimedia Commons

Low Lead in Arizona Condors

Condor_bloodwork_webIt’s been a good year for lead levels in condors in Arizona and Utah. While last year saw the second worst levels on record, this year saw the lowest level in a decade, says a press release from the Arizona Game and Fish Department.

“The ups and downs of lead poisoning over the years demonstrate that any single season does not make a trend, but our test results are encouraging,” said Eddie Feltes, field manager for The Peregrine Fund’s condor project in the release. “If this ends up being the beginning of a trend, we hope it will continue.”

Arizona Game and Fish, as well as the Peregrine Fund, which also distributed the release, believe that voluntary lead ammunition measures in the two states has contributed to the lower lead levels in condors there. Another factor may be the unseasonably mild winter, the release says.

In an article in the Salt Lake City Tribune, Chris Parish, condor program coordinator for The Peregrine Fund is quoted as saying, “The half life of lead in blood is a very short period. That gives us a relatively good indication of where and when exposure may have happened.”

The Tribune article also says that 78 percent of hunters in condor country who were contacted were voluntarily using non-lead ammunition. In 2011 the number was 10 percent.

More details in the Arizona Game and Fish press release here. (Halfway down the page.)
The same press release is here on its own page at the Peregrine Fund website.
The Salt Lake City Tribune article is here.

Photo: Courtesy Arizona Game and Fish Department

 

 

 

 

Birds Obey Speed Limits

How Did the Animal Cross the Road? The Shocking AnswerCanadian researchers found that European birds flee before an approaching car at an interval that is consistent with the road’s speed limit, but not with the actual speed of the approaching car. So birds on a highway fled sooner than birds on local, residential roads. The researchers studied roads in three speed categories.

There are conservation implications for this finding, as an article in AAAS’s ScienceShot says.

Read the ScienceShot article here.
Read the abstract in Biology Letters, here. (Full article requires subscription or fee.)

19 New Protected Species in Nova Scotia

plymouth gentianNineteen new species have been added to Nova Scotia’s list of species at risk, bringing the total listed in the province to 60, according to a Nova Scotia Department of Natural Resources press release and a CBC News report.

Three bat species are on the list, including the little brown bat, the northern bat and the tri-colored bat, which are all listed as endangered. Three bird species have been added to the list as endangered: the barn swallow, Bicknell’s thrush, Canada warbler, and the rusty blackbird. The olive-sided flycatcher and the eastern whip-or-will have been listed as threatened.

The black ash tree is listed as threatened. There are only 12 known mature trees in the province, the department press release says.

For the complete list of species, see the Nova Scotia DNR website, here. (New species are marked with the year 2013.)

Read the Nova Scotia DNR press release here.
Read the CBC News story here.
The web page with the complete list of at risk species is here.

Photo: The Plymouth gentian has been listed as endangered in Nova Scotia. Courtesy of the Nova Scotia DNR.

The Word on Birds

ovenbirdThe recent issue of The Auk (subscription or fee required to read full articles) has several articles of interest to state wildlife biologists:

It has long been assumed that early successional forests are important habitat for young ovenbirds. A paper by Andrew Vitz, now with the Massachusetts Division of Fisheries and Wildlife, tested that hypothesis experimentally. He found that the density of understory vegetation was a factor in the birds’ survival, but that the birds could do well in smaller patches of early successional habitat, such as microhabitats within mature forests.

Read the ovenbird paper here.

A paper on California spotted owls found that two is the magic number for a number of offspring. Owls that were part of a pair of nestlings had higher survival rates that onlies or triplets. The research also found that the number of young produced is a good indicator of habitat quality.

Read the spotted owl paper here.

Piping plovers hatched earlier in the season in the Great Lakes region had a higher survival rate than those born later in the season, another paper reported. Nest sites that were closer to trees also had lower survival rates. The older the plover chicks were, the more likely they were to live another day. Because the Great Lakes population of piping plovers is federally endangered (with other populations being threatened), these factors can help inform management strategies.

Read the piping plover paper here.

Photo: ovenbird, courtesy Wisconsin Division of Natural Resources

 

Razorbills Take A Florida Vacation

razorbill

Razorbills are typically birds of the northern Atlantic Ocean. Some winters they’ll show up in New Jersey or as far south as Virginia, giving bird-watchers a thrill. This black-and-white auk is not quite like anything else seen on the East Coast.

So imagine the surprise when razorbills started showing up in Florida. Not just one or two, but well over a hundred of them.

eBird had the story on their blog two weeks ago. The photo of razorbills flying over palm trees is worth a look.

The Florida media is catching on as well. Florida Today ran a story the day after Christmas. It says the birds are “penguin-like.” Well, the razorbills are black and white, and are bowling-pin shaped, but they fly. (And are from a different hemisphere, but that’s a mere detail.)

EBird says that the razorbills probably did not head south for warmth, mojitos or a vacation, but in search of food. That’s not good news.

Read the eBird blog, here.
Read the Florida Today story, here.

Photo: Razorbill, somewhere in the north Atlantic, courtesy of the US Fish and Wildlife Service.

NM Crane Mystery

mystery crane NMIt’s not so much of a mystery, as a quirky little crane that has attracted media attention nationwide. Back in November, Bosque del Apache National Wildlife Refuge in New Mexico posted a photo on its Facebook page of a crane that was darker, thinner, smaller and had more compact feathers than the flock of sandhill cranes it was with.

The refuge is known for its sandhill cranes, so it made sense that this was simply a color morph, or a crane that had preened dark mud into its feathers. But the guessing game had begun, with the most outrageous guess supposing that this was a hybrid between a sandhill crane and a trumpeter, native to South America.

The photo of the bird that is getting the most exposure is by Clint Henson of the New Mexico Department of Game & Fish.

Read more about the guessing game in the San Francisco Chronicle, here.
The Bosque del Apache NWR Facebook page is worth a visit just for the many stunning photos, of cranes, other creatures and beautiful vistas.

Photo: Mystery crane and sandhill friends, courtesy of the Bosque del Apache National Wildlife Refuge.

Avian Malaria in Alaska

Human beings do not get avian malaria, which is a good thing for the human beings in Alaska. Avian malaria is, however, caused by a parasite that is closely related to the one that causes human malaria, and that might be a good thing, too. Of course, the news for birds is bad all around.

A study by San Francisco State University researchers, published in the journal PLoS ONE, collected blood samples from birds in Alaska over a latitudinal gradient in Alaska, from 61°N to 67°N, and found the avian malaria parasite as far north as 64°N.

This is a huge threat to the Arctic’s rich bird life, because the birds there have never been exposed to avian malaria and they may be highly susceptible to it, says San Francisco State University Associate Professor of Biology Ravinder Sehgal, one of the study’s co-authors.

The finding may supply medical researchers with a valuable model of human malaria and climate change. The spread of malaria (the human kind) is one of the most threatening aspects of climate change on human health.

For anyone charged with managing populations of wild birds — whether they are songbirds, water fowl or upland game birds, the presence of avian malaria at up to a latititude of 64°N is worth noting in hunting plans, endangered species recovery plans, and when investigating disease outbreaks in birds.

Read the PLoS ONE paper, here. (This is an open access journal.)
Read the SF State U press release, here.
Read a brief analysis of the findings in Climate Central, here.

Photo: SF State Associate Professor of Biology Ravinder Sehgal holds a Common Redpoll, one of several bird species in Alaska researchers discovered were infected with malaria. Credit: Ravinder Sehgal, SF State.

Cat People vs. Bird People

When it comes to feral cat colonies versus bird conservation, there is not a lot of middle ground, reports a new study in PLoS ONE by researchers from North Carolina State University.

The study surveyed 577 people who either manage a feral cat colony or are a bird conservation professional. The big finding was that fewer than 10 percent of the cat colony managers believe that feral cats harmed bird populations or carried diseases.

The cat people were the optimists, however, the study showed. 80 percent of the cat people believed a compromise between the needs of feral cats and bird conservation could be reached, while only half the bird conservationists thought so.

We found the article on NewsWise. You can read it here.
It’s from a NC State U. press release, which you can find here.
Go to the article itself, in PLoS ONE, here. (Open access, so it’s free.)

Photo: Cats in a feral colony sun themselves on a wall. Photo courtesy of Alisa Davis, University of Hawaii at Manoa, via the North Carolina State University.