Wind turbines generating power and problems for northern new york

A hot topic today is reducing our depedency on fossil fuels through expansion of renewable energy resources like wind, water, solar, and geothermal heat.  This is both a possible and a necessary action that is important for national security and the environment. So what's the hold-up?

Here along the upper St. Lawrence River we currently have one wind power generation station installed on Wolf Island - at the outflow of Lake Ontario and the mouth of the St. Lawrence. There are a few inland in the region as well, but none close to shore on the U.S. side.  From what I can tell, Americans support wind energy until its in their own backyard. Sometimes this is a valid argument, but less for the common selfish reasons that we see more often.

Wind power station on Wolf Island

The Wolf Island wind power station has been met with some success: it is generating power, but it's also potentially disrupting bats and bird movement. The ultra sonic noise disrupts bat behavior by causing a malfunction in their ecolocation abilities. As a result, they will fly right into the turbines. Other birds - notably the colonial waterbirds on the St. Lawrence and Lake Ontario, often end up dying via head-on collisions because the wind turbines are right in their flight paths between roosting and feeding areas.  But we still don't quite have exact figures on bat and bird mortality. Once this information is compiled, we can have a better understanding of how these turbines impact regional wildlife.

Sulfur regulates methylation of mercury in aquatic environments

If you've ever read a post on this blog, you know that methylmercury is the inorganic species of mercury most toxic and bioavailable to wildlife. But we haven't discussed regulation of methylmercury in the environment - an important process partly regulated by global sulfur dioxide emissions and deposition. Of course to most chemists sulfur  regulation of methylmercury is nothing new, but to fisheries biologists it's actually pretty interesting.

Source: http://www.timemastermd.com/?tag=natural

A group of researchers lead by Dr. Drevnick of the University of Miami were recently puzzled when they found that mercury concentrations in northern pike (Esox lucius) from Isle Royale in Lake Superior had declined significantly over the past decade. They were puzzled because atmospheric deposition - the predominate route of mercury loading  in Isle Royal lakes - had remained steady or slightly increased over the last several decades.  In fact, sediment core samples indicate an increasing trend of Hg deposition around Isle Royale for the past hundred years.  But despite increasing Hg deposition, Drevnick's study found that pike from 6 interior lakes having recent fish consumption advisory warnings for Hg contamination had all declined below the mercury advisory thresholds.

Intra-annual variation in Hg threatens waterbird reproduction

Many species of wildlife are at risk to mercury bioaccumulation. Wildlife dependent on aquatic ecosystems are at a particularly high risk because mercury often ends up in runoff entering streams and lakes and  because conditions in aquatic environments enhance production of Methylmercury (MeHg); the most toxic form of Hg for wildlife. This means that managers often pay careful attention to monitoring Hg in aquatic environments - but how do they know the best time of year to monitor?

Ariel photo looking East into San Francisco Bay, California from the Pacific Ocean

Ecotoxicologists: heed this advice!

As my readers likely know by now, seabirds are often used as bioindicators of contaminants in aquatic ecosystems. Such studies rely on the fact that contaminants are ingested through contaminted prey so that contaminants in seabirds are reflective of the local diet - and ecosystem. But it turns out that linking contaminant exposures to diet in seabirds is more tricky then  many biologists realize.

A recent paper by Alexander Bond discusses the utility - or futility - of comparing diet and contaminant signatures within feathers of seabirds. Such studies often rely on stable carbon and nitrogen isotopes to evaluate diet.

Asian Carp are knocking at the (electric) fence

It's been sometime since this blog has talked about looming threats to the Great Lakes Basin. Unfortunately the reality is that there continues to be a multitude of environmental issues knocking at the locks- or in this case, the electric fence barrier in Chicago.

A couple species of exotic and invasive Asian Carp have made their way up the Mississippi River and are posed to get into Lake Michigan via the Chicago Lock's. The threat has alarmed everyone from scientists to fisherman and recreational boaters because once into the lake, this fast-growing filter feeder would severely disrupt phytoplankton production and potentially cripple the commercial and sportfish industries. To boot, the Asian Carp responds to danger (i.e. boat engines) by jumping out of the water, sometimes injuring boaters. Imagine water skiing and having to dodge jumping fish!

The voracious plankton feeders wer first introduced to fish aquaculture pens down in Arkansas to control algae blooms and parasites, supposedly 'improving water quality'. Unfortunately this has become a classic example of biological introductions gone wrong.

Every spring during reproduction, birds have a decision to make: should they use nutrients derived locally for egg production, or use reserves transported to the breeding ground? Well, it's actually not so much a choice as it is a matter of species life history.  But for aquatic toxicologists, knowing what strategy a species prescribes to is critical if one chooses to sample eggs for contaminant analysis.

A pathway for contamination

Common terns are obligate piscivores, meaning they feed almost exclusively on fish. What this also means is that they are near the top of the food chain and at high risk to contaminants that biomagnify  from one trophic level to the next. Polychlorinated Biphenyls (PCBs) are one of these biomagnifying contaminants, and to date no study has elucidated the biological pathway of PCBs from their discharge into the environment to ultimate accumulation in terns.

A recent study by M. Ward from the University of Illinois has attempted to describe this biological pathway using a population of common terns breeding within a naval station harbour on Lake Michigan, Illinois. Terns are endangered in Illinois and because PCBs can impact fitness, reduce reproductive success, and in some cases lead to mortality, it is useful to understand how they accumulate in terns.