Tuesday, January 3, 2012

Observations From the Back Row

Posted by Rich Kozlovich

DDT Today

Living Sanibel: Brown Pelicans
Widespread use of DDT to control the Florida mosquito population altered the calcium metabolism in pelicans and other birds, causing them to produce eggs with shells too thin to support the embryo to maturity. In nearby Louisiana (where, ironically, the pelican is the state bird) the population completely collapsed because of the overuse of these pesticides. Louisiana had to import Florida pelicans through the 1980s to help rebuild its decimated flocks. Today, they are once again rebounding from yet another manmade disaster, the Deepwater Horizon oil spill.

Brown pelicans not harmed by DDT either
By Steve Milloy

Thanks to Florida journalist Charles Sobczak for the opportunity to debunk another DDT myth. The Sanibel-Captive Island Leader reports, …Widespread use of DDT to control the Florida mosquito population altered the calcium metabolism in pelicans and other birds, causing them to produce eggs with shells too thin to support the embryo to maturity. In nearby Louisiana (where, ironically, the pelican is the state bird) the population completely collapsed because of the overuse of these pesticides. Louisiana had to import Florida pelicans through the 1980s to help rebuild its decimated flocks. Today, they are once again rebounding from yet another manmade disaster, the Deepwater Horizon oil spill…

But check out the following from JunkScience.com’s “100 Things You Should Know About DDT“:
92. Brown pelicans declined in Texas from a high of 5,000 birds in 1918 to a low of 200 in 1941, three years before the presence of DDT. [Pearson TG. 1919. Review of reviews. Pp. 509-511 (May 1919); Pearson TG. 1934. Adventures in Bird Protection, Appleton- Century Co., p. 332; Pearson TG. 1934 (Discussion of 1918 survey) National Geographic pp. 299-302 (March 1934); Allen RG. 1935. Auk 52: p.199;]

93. Disappearance of the brown pelicans from Texas was attributed to fisherman and hunters. Gustafson AF. 1939. Conservation in the United States, Comstock Publ. Co., Ithaca, NY. (Repeated in U.S. Fish and Wildlife Service Report No. 1, 1970)]

94. Brown pelicans experienced no difficulty in reproducing during the DDT years. [See Banks, RC. 1966. Trans San Diego Soc Nat Hist 14:173-188; and Schreiber RW and RL DeLong. 1969. Audubon Field Notes 23:57-59]

95. Brown pelicans did suffer reproductive problems following the 1969 Santa Barbara oil spill. Oil on eggs is a known cause of embryo death. [See e.g., National Wildlife Federation . 1979. Embryonic mortality from oil on feathers of adult birds. Conservation News, pp. 6-10 (October 15, 1979); Hartung, R. 1965. (Oil on eggs reduces hatch ability by 68 percent). J Wildlife Management 29: 872-874; King, KA 1979. (Oil a probable cause of pelican mortality for six weeks after spill). Bull Environ Contam. Toxicol 23:800-805; and Dieter, MP. 1977. (5 micro liters of oil on fertile egg kills 76 percent to 98 percent of embryos within. Interagency Energy-Environment Research and Development Program Report, pp 35-42]

96. Among brown pelican egg shells examined (72 percent), there was no correlation between DDT residue and shell thickness. [Switzer, B. 1972. Consolidated EPA hearings, Transcript pp. 8212-8336; and Hazeltine, WE. 1972. Why pelican eggshells are thin. Nature 239: 410-412]

97. An epidemic of Newcastle disease resulted in millions of birds put to death to eradicate the disease. [United Press International. "Newcastle disease epidemic in California (April 1972)] The epidemic among U.S. birds was caused by the migration of sick pelicans along the Mexican coast. [Hofstad MC. 1972. Diseases of Poultry. Iowa State Univ. Press]

Christmas Bird Count Illuminates an Old Fable
The National Audubon Society is in the midst of its annual "Christmas Bird Count," which is mostly an unscientific "bird feeder" bird count done when those birds which are at greatest risk of decline (i.e. neo-tropical migrants including most grassland birds) are actually down south in Mexico, the Caribbean and Central and South America. In short, this is the wrong time of year to count birds that are truly at risk!

That said, the 111-years worth of data collected by the "Christmas Bird Count" does have some use, if for no other reason than to prove that one of the biggest fables about Bald Eagles and Osprey is more than a small lie. What's the story? Simple: that Bald Eagles and Osprey were pushed to the edge of extinction by DDT. Not True.

Editor’s Note: I posted this link for two reasons. This person actually was involved in bird counting data and I want to recommend reading the comments! Although he is an anti-DDT guy this exchange clearly shows the intellectual dishonesty of those who have a constant drumbeat against DDT. They are nothing more than time wasters as this author points out. I might add that he is mistaken that the elimination of DDT was beneficial for birds. During the DDT years the bird population increased many times and the robin, which according to Rachel Carson was going to be destroyed by DDT, was probably the most populace bird in North America. RK

ESA Today

Feds are warned of lawsuit over wood stork's "endangered" listing
Attorneys with Pacific Legal Foundation today formally warned federal officials that they will be sued if they do not immediately drop the unjustified listing of the wood stork as "endangered" under the U.S. Endangered Species Act. In a letter mailed today to the U.S. Fish and Wildlife Service (FWS), PLF attorneys point out that the federal government's own scientific findings concluded that the "endangered" classification for the wood stork is no longer warranted.

Biodiversity: New bluefin tuna fishing rule challenged
Recreational anglers clean a haul of tuna at a marina in Venice, Louisiana. Conservation advocates say increase take will speed demise of rare fish —Conservation advocates are challenging a new fisheries rule that increases the take of rare Atlantic bluefin tuna, a species already under pressure from overfishing and illegal commerce driven in part by Japan’s nearly insatiable demand for sushi-grade tuna



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