Monarch Pops Plummet

Monarch_butterflyThe Washington Post reports that the monarch butterfly population wintering in Mexico has shown a drop in six of the last seven years. “…There are now only one-fifteenth as many butterflies as there were in 1997,” the article says.

Journey North reports that this year’s population is lowest since record-keeping began.

Drought and herbicides that have killed off milkweed, which the monarchs require as host plants — particularly in the Midwest, are thought to be the main contributors to the decline. While populations have rebounded after drops, the overall trend is down, down, down.

Read the Washington Post article here.
Read an Associated Press article here.
The Journey North Facebook page is here.

Photo: Monarch butterfly by Mark Musselman, used courtesy of the US Fish and Wildlife Department.

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

 

Water Users v. Cranes in Texas

whooping cranes at Aransas NWRIn 2009, 23 federally endangered whooping cranes died because of a drought. A recent court ruling says that this is an illegal take of a federally-endangered species, and that the federal law has precedence over Texas state law, which says that water is doled out on a first come, first served basis, says an article in Bloomberg.

The Texas state agencies will appeal the ruling, the article says.

The whooping crane flock in question is the world’s only self-sustaining wild flock, the article says, migrating from Canada to Texas. The article also implies that what was once “an isolated stretch of Texas coastal marsh,” where a tiny flock of whooping cranes survived unnoticed at a time when the species was thought to be extinct, is now home to the “world’s largest concentration of refineries and petrochemical plants.”

Read the Bloomberg article here.

Photo: Whooping cranes at Aransas National Wildlife Refuge, by Steve Hillebrand, courtesy US Fish and Wildlife Service.

 

White Nose Syndrome in Georgia

cumberland gap wns batAccording to a Georgia Department of Natural Resources press release:

The Georgia Department of Natural Resources, the National Park Service and the U.S. Fish and Wildlife Service announced today that bats with white-nose syndrome were found recently at two caves in Dade County.

 

A National Park Service biologist and volunteers discovered about 15 tri-colored bats with visible white-nose symptoms in a Lookout Mountain Cave at Chickamauga and Chattanooga National Military Park in late February. On March 5, a group led by a Georgia DNR biologist also found tri-colored bats with visible symptoms in Sittons Cave at Cloudland Canyon State Park.

This news follows quickly on the announcement just yesterday that white nose syndrome had been found in South Carolina. The Georgia Department of Natural Resources release says, and the U.S. Fish and Wildlife’s WNS map confirms, that Dade County, Georgia is contiguous with counties in Alabama and Tennessee that confirmed WNS last year.

I’ll sometimes say that “it’s white nose season,” but what that means may not be clear if you haven’t been following WNS closely. This is a cold-loving fungus that requires low temperatures to become symptomatic in bats. WNS is typically detected at the end of winter, particularly in southern locations or in places where the infection is in its early stages. Add in time for a laboratory to analyze the bat to confirm WNS, and you are usually looking at a window of March through June for announcements of new WNS sites.

Read the Georgia DNR release here.
Find the USFWS map here. (Look carefully at the northwest corner of Georgia.)
If you want traditional media, there is a short piece in USA Today, here.

Photo: An eastern pipistrelle bat — aka tri-colored bat — found at Cumberland Gap National Historical Park (in Kentucky, Tennessee and Virginia) shows visible signs of white-nose syndrome. Courtesy of the National Park Service

White Nose Syndrome in South Carolina

SC WNSA tri-colored bat, found dead in Table Rock State Park in the northwestern corner of South Carolina, has been confirmed to have white nose syndrome (WNS), the Charlotte Observer and S.C. Department of Natural Resources report.

The SC DNR press release says:

The bat was collected on Feb. 21, transported on ice, and submitted to the Southeastern Cooperative Wildlife Disease Study in Athens, Ga. The Wildlife Disease Study confirmed the presence of Geomyces destructans fungus, which causes WNS.

 

It further says:

“We have been expecting WNS in South Carolina,” said Mary Bunch, wildlife biologist with the S.C. Department of Natural Resources (DNR) based in Clemson. “We have watched the roll call of states and counties and Canadian provinces grow each year since the first bat deaths were noted in New York in 2007.”

South Carolina is the 21st state to report a case of WNS. The roll cal includes five Canadian provinces. The U.S. Fish and Wildlife Service’s WNS map shows this newest WNS site as being located in the Appalachian Mountains, not far from many other Southern mountain sites in North Carolina, Tennessee, Kentucky and Virginia.

Read the Charlotte Observer article here.
Read the SC DNR press release here.

Illustration: The USFWS March 11, 2013 WNS map, showing a new site in Pickens County, South Carolina confirmed. Map by Carl Butchkoski, PA Game Commission

Lizards and Climate Change

shortHornedLizardTwo papers in the journal Global Ecology and Biogeography* outline two threats that the increased local temperature aspect of climate change makes on lizards.

The first paper is about lizards in South America, but North American reptiles might experience something similar. Bearing live young allowed lizards to occupy colder climates, the paper says, but those species are now limited to those climates. As temperatures rise, those species will be forced either closer to the pole(s) or to higher elevations — severely limiting available habitat.

Read the paper The evolution of viviparity opens opportunities for lizard radiation but drives it into a climatic cul-de-sac, here. (Fee or subscription needed for full article.)
Read the University of Exeter press release on EurekAlert, here.

Another paper in the journal took data on the body temperature of lizards and compared it to the temperature of their environments. It found that it was the temperature of the environment, not the species’ body temperature, that correlated most closely (either positively or negatively) with important life-history factors such as clutch size and longevity.

Because environmental temperature seems to play a bigger role than body temperature (and therefore the lizards’ ability to compensate for environmental temperature), the paper says, climate change can have a “profound influence on lizard ecology and evolution.”

Read the paper Are lizards feeling the heat? here. (Fee or subscription required for full article.)

*In this case it is a coincidence that I ran two items from this journal on consecutive days. I received alerts on these papers from two different sources. Go figure. I’ll try to make next week lizard- and biogeography free.

Photo: The viviparous North American species the short-horned lizard, courtesy of the National Park Service.

How Vertebrates Invade

lizardrainbow_500x328If Junior decides that his cool new pet isn’t all that cool, and his parents decide that the best way to get rid of it is to let it go in the backyard, what are the chances that it will become an invasive species?

In a recent paper in the journal Global Ecology and Biogeography, researchers from the University of Nebraska studied both successful and unsuccessful introductions of non-indigenous vertebrate species in Florida.

For reptiles and amphibians, the biggest predictors of establishment were a small body size and a wide range in their homelands. For fish, the biggest factor was if there were other members of the fish’s genus present. Mammals became established when there were other non-native species already in the habitat. No clear pattern was detected for birds.

This research certainly doesn’t explain Florida’s python invasion, but it can provide valuable ideas for analyzing the risk of known releases or in creating importation white lists and black lists.

Read the Global Ecology and Biogeography abstract here. (Full article requires a fee or subscription.)

Photo: Rainbow lizard. Small(ish). Check. Wide range in its native land. Check. Established population in Florida. Check. Photo by Kevin M. Enge, used courtesy of the Florida Fish and Wildlife Commission.

California Bites the Bullet

condor_ScottFrierCalifornia banned lead ammunition within the range of the endangered California condors (Gymnogyps californianus) in 2008. Now environmental groups are moving to take the ban statewide to protect the condor and other large scavenging birds such as bald eagles from lead poisoning. The National Rifle Association protests.

An article in the San Jose Mercury News reports the NRA saying that because copper bullets cost $40 a box and don’t fly as true, while lead bullets cost $20 a box, the ban is equivalent to a ban on hunting, and that the groups’ ultimate goal is to ban guns. (The article also quotes an Audubon spokesman saying that of course the group does not oppose either hunting nor guns.)

An article in the British newspaper The Guardian links to a recent Proceeding of the National Academy of Sciences paper detailing the condors’ vulnerability to lead poisoning from ammunition. It seems the condors are such effective scavengers that even if only one percent of the carcasses or gut piles contain lead ammunition, 30 to 50 percent of the condors will feed from one of them.

Read the San Jose Mercury News article here.
Read The Guardian article here.
Find the PNAS abstract here. (Fee or subscription needed for full access.)

Photo: California condor by Scott Frier, courtesy Arizona Game and Fish Department

Bumblebee History

cleptoparasitic beeOther native bee populations in the Northeast are holding up better than bumblebees (genus Bombus), a new paper in the Proceedings of the National Academy of Sciences reports.

The study looked at over 30,000 museum specimens spanning 140 years. It found that species richness of bees in the region declined weakly overall. However, three species declined sharply, all the the genus Bombus. The study also showed that there were significant shifts in species abundance over time, with 29 percent of the species decreasing and 27 percent increasing.

Unfortunately, the bees that showed the greatest increase were exotic species. Also doing well were southern species on the northern edge of their range.

In a EurekAlert press release, lead author Ignasi Bartomeus is quoted as saying, “Environmental change affects species differentially, creating ‘losers’ that decline with increased human activity but also ‘winners’ that thrive in human-altered environments.”

The scientist found that the more vulnerable species tend to have larger body sizes, restricted diets, and shorter flight seasons.

Read the EurekAlert press release here.
Read the PNAS abstract here. (Access to the paper requires a subscription or a fee.)

Photo: The cleptoparasitic bee Coelioxys sayiis is widely distributed in North America and parasitizes Megachile leaf-cutter bees. This photo was taken in Prospect Park in Brooklyn, N.Y. by John Ascher, of the American Museum of Natural History. Used courtesy of AMNH.

White Nose Syndrome in Illinois

Illinois WNS mapWhite nose syndrome (WNS) in bats was detected in four Illinois counties in February, the Chicago Sun-Times reports. The US Fish and Wildlife Service’s WNS map shows that the new sites in southern Illinois are near other sites in other states, while the site in the northern part of the state stands alone (although it is somewhat near last year’s unconfirmed Iowa site).

The article notes that Illinois is the 20th state to be struck by WNS.

The Illinois Department of Natural Resources press release says that the bats found with WNS were little brown bats and northern long-eared bats.

Read the Chicago Sun-Times article here.
Read the Illinois DNR press release here.
See the updated WNS map from the US Fish and Wildlife Service here.

In addition: the suspected case of WNS on Prince Edward Island in Canada, which we reported on last month, has been confirmed to be WNS.

Read the article on the CBC website, here.

(‘Tis the season for WNS reports. It generally runs from March through June, so stay tuned.)

Map: Cal Butchkoski, PA Game Commission, used courtesy of US Fish and Wildlife Service