News from Scientists at the USGS Patuxent Wildlife Research Center
Monday, June 16, 2003
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Sparling Meets with Visiting Scientists from the Caribbean Concerning Declining Amphibians On June 19, Don Sparling consulted with visiting scientists from Dominica and Trinidad concerning declining amphibian populations in these Caribbean island nations. It seems that one species commonly referred to as the Mountain Chicken, is declining in part at least to infections from chytrid fungus. Sparling provided some references and advice to the scientists. Contact Don Sparling, Laurel, MD, 301-497-5723 Sparling to Participate in Workshop on Developing Protocol in Amphibian Biological Screening On June 24-25, Don Sparling will participate in an international workshop on developing a protocol to use amphibians in biological screening of new chemicals for thyroid disrupting effects. The meeting will be held in Duluth, MN and is an extension of Dr. Sparling's participation in an OECD sponsored conference in Paris, France about two years ago. Contact Don Sparling, Laurel, MD, 301-497-5723 Patuxent Hosts a Visiting Scientist from Spain Manuel Ortiz Santaliestra has arrived at Patuxent Wildlife Research Center as a visiting scientist from the University of Salmanca, Salmanca Spain. Mr. Santaliestra will be here through September to study techniques of amphibian ecotoxicology with Don Sparling and to collaborate on a project. Contact Don Sparling, Laurel, MD, 301-497-5723 Publication by Patuxent Scientist:
Estimation of ocelot density in the
Pantanal using capture-recapture analysis of camera-trapping data Contact Marc Kery, Laurel, MD, 301-497-5579 Publication by Patuxent Scientist: Spring hunting changes the regional movements of migrating greater snow geese. Authors: Béchet, A., J.-F. Giroux, G. Gauthier, J. D. Nichols, and J. E. Hines. 2003. Journal of Applied Ecology 40(3):553-564. Human-induced disturbance such as hunting may influence the migratory behavior of long-distance migrants. In 1999 and 2000 a spring hunt of greater snow geese (Anser caerulescens atlanticus) occurred for the first time in North America since 1916, aimed at stopping population growth to protect natural habitats. We evaluated the impact of this hunt on the staging movements of geese along a 600-km stretch of the St. Lawrence River in southern Quebec, Canada. We tracked radio-tagged female geese in three contiguous regions of the staging area from the south-west to the north-east Lake St Pierre, Upper Estuary and Lower Estuary, in spring 1997 (n = 37) and 1998 (n = 70) before the establishment of hunting, and in 1999 (n = 60) and 2000 (n = 59) during hunting. We used multi-state capture-recapture models to estimate the movement probabilities of radio-tagged females among these regions. To assess disturbance level, we tracked geese during their feeding trips and estimated the probability of completing a foraging bout without being disturbed. In the 2 years without hunting, migration was strongly unidirectional from the south-west to the north-east, with very low westward movement probabilities. Geese gradually moved from Lake St Pierre to Upper Estuary and then from Upper Estuary to Lower Estuary. In contrast, during the 2 years with hunting westward movement was more than four times more likely than in preceding years. Most of these backward movements occurred shortly after the beginning of the hunt, indicating that geese moved back to regions where they had not previously experienced hunting. Overall disturbance level increased in all regions in years with hunting relative to years without hunting. Synthesis and applications: We conclude that spring hunting changed the stopover scheduling of this long-distance migrant and might further impact population dynamics by reducing prenuptial fattening. The spring hunt may also have increased crop damage. We propose that staggered hunt opening dates could attenuate secondary effects of such management actions. Contact James Nichols, Laurel, MD, 301-497-5660 |
Patuxent's Home Page has a New Look!
The Patuxent Wildlife Research Center is pleased to announce a new look for its web presence. A completely revamped home page (http://www.pwrc.usgs.gov) and second-level pages were launched on May 19, 2003. We hope users will find the new approach to be more visually appealing, user-friendly, and relevant than our previous version. It is designed to serve both the technical and non-technical user, and we have built in enough redundancy so that users seeking specific information should be able to locate it easily from a variety of entry points. The Center Web Committee, chaired by Bill Bauer, greatly benefited from the elegant work performed by just-graduated University of Maryland web design student, Kimberly Carter, who developed many alternative designs and educated the Committee about the technical and customer-use implications of different approaches. Lois Loges also played a crucial role, contributing countless hours setting up and fine-tuning the site. However, as all web sites should be, ours is and will continue to be a work in progress. We will appreciate any suggestions for further improvement. Contact Lois Loges, Laurel, MD, 301-497-5531 Whooping Crane Update June 10, 2003: We currently have 28 very active whooper chicks ranging in ages from 2 days old to the oldest at 50 days old. Eighteen of the birds are being trained for the Whooping Crane Eastern Partnership (WCEP) migration project. All 18 have had extensive exposure to the ultralight aircraft as part of their "ground school" training, when they learn to run after the aircraft. In the fall, they will follow the ultralight in flight and be led on migration south from Wisconsin. Because the chicks all hatch at different times, they are split into two groups by age and trained separately until they all mature further and the age differences aren't as significant. The 10 oldest chicks are scheduled to be shipped to Wisconsin very soon; the last eight, which are still quite young, will be sent after they've gotten older. Current whooping crane egg production is 51 eggs from 10
producing females. Thirty eggs are known to be fertile and 26
hatched, plus 2 from eggs sent from the San Antonio Zoo, and 1 egg
from the International Crane Foundation. One whooper chick slated
from the WCEP program died, apparently from peritonitis; we are
speculating that might have been caused by the thorny-headed worm [Acanthocephalans
sp. -- More information on this parasite can be found on line in
"Cranes: Their Biology, Husbandry, and Conservation" at http://www.pwrc.usgs.gov/resshow/gee/
This is a picture of the youngest
chick we have right now. He's 1 day old in the picture.
This is a picture of our oldest WC chick. He's 50 days old in the picture. Contact Kathleen O’Malley, Laurel, MD, 301-497-5609.
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