News of the Wild: October/November 2012
Palms put rays at risk, duck numbers up and refuges boost home values
Roger Di Silvestro
How Alien Palm Trees Put Rays at Risk
Stanford University students researching marine life and birds at Palmyra Atoll, a U.S. territory in the north-central Pacific Ocean, found last year that replacing native trees there led to a decline in the number of manta rays (left) cruising coastal waters.
Through analysis of nitrogen isotopes, animal tracking and field surveys, biology students Douglas McCauley, Paul DeSalles and Hillary Young showed that replacing native trees with nonnative palms led to about five times fewer roosting seabirds (they seem to dislike nesting in palms), which led to fewer bird droppings reaching the soil below and washing into surrounding waters. The decline in sea nutrients led to smaller and fewer plankton, resulting, finally, in fewer manta rays.
The research highlights the need for nontraditional alliances—among marine biologists and foresters, for example—to address whole ecosystems across political boundaries.
Good News for Ducks
The U.S. Fish and Wildlife Service (FWS) reports that North American duck numbers are at a record high, with an estimate of 48.6 million compared to last year’s 45.6 million.
Conducted by FWS and Canadian Wildlife Service biologists, the annual count samples more than 2 million square miles of waterfowl habitat. Estimates for the north-central United States, Alaska and south-central and northern Canada indicate that mallards, gadwalls, green-winged teal, canvasbacks and lesser and greater scaup are up more than 10 percent from 2011. The news isn’t all good, however: The northern pintail, at 3.5 million birds, is down 22 percent from last year. The survey of the northeastern United States and eastern Canada shows that mallards, goldeneyes and ring-necked ducks declined.
Help us take action to protect prairie pothole wetlands for northern pintail ducks>>
Wildlife Refuges Boost Home Values
A new FWS study indicates that proximity to one of the nation’s 556 national wildlife refuges can increase a home’s value.
Economic researchers at North Carolina State University working on behalf of FWS looked at about a dozen refuges in each of three regions of the country. They found that location of a home within half a mile of a refuge and within eight miles of an urban center increased home values by roughly 7 to 9 percent in the Southeast, 4 to 5 percent in the Northeast and 3 to 6 percent in the FWS California/Nevada region.
The researchers surmised that refuges boost property values in the selected regions because refuges protect against future development while preserving scenic vistas and open spaces.