The Birds and The PCBs talks about....Birds and PCBs

When I started this blog, I didn't think I was going to literally be blogging about birds and PCBs. But apparently I wrong.

I now present you with a heartbreaking story of songbirds, toxic chemicals, and tainted love. Sigh.

Researchers have found that chickadees that are exposed to very small, allowable levels of polychlorinated biphenyls (PCBs) can’t keep a tune as well as other birds. Like many bird species, in chickadees, the females go for males with the best songs. So, PCB-exposed birds might lose out on mates, says Sara DeLeon, an ecologist at Cornell University.

The Cornell scientists examined chickadees living along New York’s Hudson River, not far from a General Electric power plant that used PCB insulators from 1907 until the 1970s, dumping some 500,000 kilograms of the toxic chemical into the river. The US government ordered GE to clean the PCB-contaminated waters, one of the country’s largest waste cleanups. Even though current levels are below EPA's regulatory limits and thus deemed "safe," traces remain in many sites on the river, and are impacting wildlife in subtle ways

PCBs, or polychlorinated biphenyls, are a class of yucky chemicals that were banned in the 1970s for being persistent organic pollutants (POPs). They are found to bioaccumulate in people and animals. They also have subtle effects in human, such as influencing sex ratios.

While the lackluster love songs of the PCB-contaminated birds could be a warning to the female chickadees that their mates aren't healthy, this could pose some serious problems for bird populations. "[E]ven female choice against chemically tainted birds, as is the case with the Hudson River chickadees, can threaten local birds if males don’t seem a good mating prospect and females move elsewhere in search of untainted love, DeLeon says. 'Populations could end up declining and birds might not end up living there.'"

And there you have it. Heartbreak, heartache, and chickadees.

Source: New Scientist

I'll have the plankton soup with my soupy swill, please

According to a report by two U.S. scientists, "Spreading Dead Zones and Consequence for Marine Ecosystems," there are 405 asphyxiating dead zones in our oceans. At this rate, one scientist says, all that will be left for the next generation to harvest from the sea is "plankton soup."

Dead zones are caused by nutrient pollution, such as fertilizer runoff from agriculture, that adds phosphates and nitrogen to the water, causing massive algae blooms. The algae then die, and sink into the ocean, where bacteria consume it, sucking up the oxygen from the water and causing what is known as hypoxia, or a dead zone.

North America's largest dead zone is in the Gulf of Mexico: a 22,000-sq-km sea morgue the size of New Jersey.

Other dead zones have been discovered off California, in Lake Erie, around the Florida Keys, in North and South Carolina creeks and in Washington's Puget Sound. Together, they have turned 246,048 sq km of the seas - an area the equivalent of all five of the Great Lakes - into marine wastelands.

Because fish and other organisms can't live without oxygen, dead zones can be extremely detrimental to the fishing industry, as well as to aquatic ecosytems.

The good news is that with proper pollution prevention dead zones may be reversible. But, if we keep going the direction that we are going, all we have to look forward to is seas emptied of fish and filled with "soupy swill" - algae, bacteria and jellyfish and their ilk - the "rise of slime." This brave new ocean will resemble ancient oceans - a soup of primeval muck where "microbes and jellyfish . . . may constitute the only surviving commercial fishery"