Saturday, June 30, 2012

more on drought

More on drought, and the response of vegetation to drought, at:

drought and bird populations, distribution, density

Ph. by Patti McNeal; Wikim. Commons
There has been some discussion recently (on the Wisconsin Birding listserv and the WI Birding Facebook page) regarding the high numbers of Dickcissels found in WI this summer – possibly reflecting drought conditions on the Great Plains. Bird distribution and density are complex phenomena, and there may be several inter-related and interlocking factors driving changes. But there is no doubt that drought affects nesting patterns of birds from multiple avian taxa groups. Here are just a few “hints” at more details:

“Nesting of Vesper Sparrows, Horned Larks and Western Meadowlarks ended abruptly in mid—June 1988 during a period of extremely hot weather. In 1987 and 1989, nesting continued into July. Despite substantial reductions in bird density and productivity during the drought, many species recovered to predrought levels 1 yr following the drought. This suggests that year-to-year fluctuations in densities of some of these species may not be tightly linked to short-term changes in local productivity. However, sequential years of low productivity may have more substantial effects on these short-lived species. Thus, if drought conditions in North American grasslands become more frequent, as some climate models predict, there could be related changes in the avifauna of the region”.

George, T. Luke, Ada C. Fowler, Richard L. Knight, and Lowell C. McEwen. 1992. Impacts of a Severe Drought on Grassland Birds in Western North Dakota. Ecological Applications 2:275–284.

A “study, also published in Global Change Biology, focused on drought, ultimately questioning the wisdom of considering all green space viable bird habitat. The amount of bird refuge is usually measured by the Normalized Difference Vegetation Index (NDVI), which measures the density of green leaves on the ground. However, since green cropland that can’t serve as bird cover during a drought still gets picked up on the index, scientists suspected there could be a better measure of refuge quality. They compared the NDVI data with 15 years of precipitation data from the North American plains. Precipitation proved to be a much more accurate indicator of population health and diversity than the NDVI. But the data also revealed that migratory bird species can experience population losses up to 13 percent during extreme droughts”.

FromHurricanes and Droughts Beat Back Migratory Bird Populations” , by S. Dowdey. Apr 2010

Wednesday, June 27, 2012

invasive plants and birds

Teasel and seeds of other invasive plants sometimes are accidentally (or maybe even purposely, but unwisely?) fed to birds. There are excellent sources of information available today to learn more about invasive plants, how to avoid spreading them, and how they have negative effects on bird populations.

Start with SEWISC (The Southeastern Wisconsin Invasive Species Consortium, Inc. (SEWISC):

US Forest Service page on Invasives:

Effects on bird communities:

Effect on nesting success:

Tuesday, June 26, 2012

hummingbird news

photo by Lee Karney
If you're watching them as I do all summer, in gardens (and less often at feeders), you may be interested in current research on hummers. Here are a few links to use to find more information: 

Hummingbird Monitoring Network
Western Hummingbird Partnership
Operation Rubythroat
Scott Weidensaul's hummingbird research

Thursday, June 21, 2012

news: Chimney Swift Working Group - Wisconsin

The WI Chimney Swift Working Group had its first meeting, with 20+state agency, NGO, county, conservation organization, and other partners from around the state in March of this year. Our second meeting is planned for mid-July; if you represent a government unit, environmental organization, or bird club and would like to be involved, please contact me (contact info given below).

Many activities will be planned around the state this year focusing on swifts. For examples from nearby states (MN is very active) see info at these links:

William P. Mueller
Western Great Lakes Bird and Bat Observatory
WGLBBO online:
Milwaukee, WI

Friday, June 15, 2012

Wood Thrush (and Song Thrush) news

(Photo by S. Maslowski)
If you share my interest in the Wood Thrush, read the excellent information linked here. Some additional fine online references can be found here and here.

(Ph: Wikim. Commons)
Similarly, Europe's Song Thrush  is faced with an array of threats and is experiencing a population decline - read about it here.

Thursday, June 7, 2012

the latest news on the Red Knot

Red Knot by Dick Daniels - Wikimedia Commons
Read about the current situation for the Red Knot, a species facing a worrisome decline, at this link.

environmental ethics

Since there are so many ethical issues raised by contemporary environmental problems, it's useful to be able to gather or describe some information here on environmental ethics. A history of some aspects of this movement and its trends in academic circles can be found here.

See also:
Ron Epstein's excellent Env. Ethics page

Stanford Encyclopedia link to Env. Ethics

Center for Environmental Philosophy

Tuesday, June 5, 2012

working for species conservation

If you're interested in helping to make progress in species conservation, go the website of the Center for Biological Diversity, and sign on to one or more of their action programs (scroll down at  this link). CBD does some of the "heavy lifting" in biodiversity conservation, often tackling controversial topics. Learn more about their programs  at this page.