Tree Swallows, Mercury Contamination, and Middle River

A Tree Swallow on our farm in Swoope. (Photo: R. Whitescarver)

Today we share a story from Bobby Whitescarver, of Whitescarver Natural Resources Management, about recent work to study and mitigate the effects of a mercury leak on tree swallows in Virginia. The research helped secure a settlement from DuPont, the synthetic fiber production plant responsible for the leak. Read the original post here 

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There are many harbingers of Spring in Swoope; the yellow blooms of daffodils and forsythia, the sounds of spring peepers, and pastures changing from brown to green are only a few. My favorite harbinger of Spring is the arrival of Tree Swallows, Tachycineta bicolor. I start looking for them in late February. This year they arrived in Swoope on March 18.

Our Tree Swallows migrated almost 2,000 miles North from Florida and Cuba. They come here to breed and raise their young, returning South in the fall.

We maintain forty-eight nest boxes for them and other cavity nesters such as Eastern Bluebirds and Carolina Chickadees. There must be a hundred Tree Swallows along Trimbles Mill Road and the Middle River. There are often two or three birds around each nest box.

Anytime we drive a truck or tractor into a pasture it disturbs insects. The Tree Swallows come to get them. They are joined by Barn Swallows, Cliff Swallows and Northern Rough-wing Swallows in the feeding frenzy. It’s an amazing show of flight with colorful dives and swoops.

The College of William and Mary Research Team
We have always had a few nest boxes but in 2005 Dan Cristol, Chancellor Professor of Biology from the College of William Mary asked us if we would participate in a research project to study the biomagnification of mercury up the food chain. He and his students put up hundreds of nest boxes along the Middle, South, and North Rivers in Augusta County. On our farm, they added thirty nest boxes to the ones we already had.

Dr. Dan Cristol, Ornithology Professor at the College of William and Mary. He is holding a Tree Swallow captured along Middle River in Swoope, VA. (Photo: R. Whitescarver)

Mercury Contamination of South River
Waynesboro, Virginia, was the site of a Dupont synthetic fiber production plant that discharged mercury into the South River from 1930 to 1950. The Middle and North Rivers were used as reference sites in the research because they didn’t have legacy mercury discharges in the River.

Tree Swallows Were the Main Species of Study
Tree Swallows were their main species of study because during the breeding season they eat only flying insects. Insects such as mayflies, dragonflies, caddisflies, and stoneflies spend their immature life in streams and rivers. The ones in the South River spent their aquatic life in the sediments contaminated with mercury. When these aquatic insects hatch from the water becoming flying insects, many are eaten by Tree Swallows. Subsequently, they feed their babies these insects and they, in turn, ingest the mercury.

Their groundbreaking research was published in Science magazine in the April 2008 edition. The article, “The Movement of Aquatic Mercury Through Terrestrial Food Webs,” states,

“Mercury is a persistent contaminant that biomagnifies up the food web, causing mortality, reproductive failure, and other health effects in predatory wildlife and humans.”

Their studies proved that mercury, in fact, does biomagnify up the food chain; twenty times higher than in the reference birds on our river.

Their six years of field research was, to their knowledge, “the first study to suggest disruption of multiple endocrine functions by mercury in wild animals,” one research paper attests. Cristol and his students published over fifty papers on their findings of mercury in wildlife.

Dr. Cristol taking scientific measurements on a Tree Swallow. (Photo: R. Whitescarver)

Mercury Greatly Reduced Tree Swallow’s Ability to Withstand Heat
“The mercury-exposed swallows suffer a reduced hormonal response to stress, altered thyroid hormone levels, suppressed immune system, twenty percent fewer offspring annually, and most interestingly, a greatly reduced ability to withstand heat waves. Normally hot weather is great for them because of the increased number of insects flying around, but on the contaminated sites, that is when the babies tended to die…so there is trouble ahead when mercury and global climate change run into each other,” Cristol wrote.

The William and Mary field research ended in 2010 but we still maintain the nest boxes and added even more. It is a joy to see their metallic blue/green upper bodies and white breasts flying around the pastures in pursuit of insects.

Largest Natural Resource Damage Settlement in Virginia History
Their research was used as part of the South River/South Fork Shenandoah River Natural Resources Damage Assessment Plan which led to a settlement from Dupont of $48 million to various environmental organizations to improve our landscape and waters. This is the largest natural resource damage settlement in Virginia history and the eighth largest in US history.

The College of William and Mary was a member of the South River Science Team that used research to understand, educate and reduce the effects of mercury in the South River.

We are very proud to have been a small part of this massive research project that resulted in some form of environmental justice for the decades of mercury contamination of a major river.

Read the original post here 

We are what we eat: Scientists probe the potential effects of emerging contaminants

When contaminants get into the water system, some people might assume that standard water treatment techniques would make that water free from potential contamination.

The truth is, it is not that simple.

What happens when detergents, flavors, fragrances, hormones, medications, new pesticides, veterinary medicines, and other chemicals make their way into waterways of the Great Lakes Basin? Researchers are exploring these contaminants of emerging concern, or CECs, to help us better understand the potential impacts on wildlife and people.

For example, consider a commonly used over-the-counter pain reliever. Sunlight, temperature, pH or microbial activity will naturally break it down into different smaller compounds. Those smaller compounds, and the medication itself, are collectively termed “contaminants of emerging concern.”

Between the years of 2010 and 2014, our agency, the U.S Geologic Survey, and the Environmental Protection Agency (EPA) set out to characterize emerging contaminants present in Great Lakes Tributaries.  From 2015 to the present investigations have focused on assessing hazards and impacts these contaminants have on fish and wildlife species.

Daniel Gefell, biologist for the USFWS, holding a Bowfin at one of the sampling sites, USFWS.

Funded by the Great Lakes Restoration Initiative, collaborators sampled water, sediment, and fish populations from a variety of different Great Lakes field sites. In New York, field efforts were primarily focused in the Rochester area and in the North Country in the St. Lawrence river drainage.

The most consistently studied organism is fish, with few studies directed toward the toxic effects in freshwater mussels, freshwater aquatic plants, or other native aquatic species. Four approaches were taken to evaluate fish populations and the effects of emerging contaminants.

1)         Biologists measured over 200 sampling sites and found that many of these emerging contaminants are consistently present in the water and sediment within the Great Lakes Tributaries.  From this information, biologists determined which chemicals are most often detected and at what levels so they could mimic environmental conditions with laboratory studies.

2)         In the same places where CECs were found, wild fish populations were evaluated for indicators of poor health including changes in physical appearance and reproductive health.

Drawing blood from a fish to send in for CEC analysis, USFWS.

3)         Unexposed hatchery raised fish were caged and placed in the same areas where CECs were found and where wild fish were evaluated.  Hatchery fish were used because they were unexposed to CECs before the evaluation.  Biologists then compared hatchery fish to the wild fish to help determine the impacts of CECs on their health.

4)         Biologists looked at previous scientific publications of field and laboratory studies to take advantage of all the information we know about individual chemicals and their effects on fish. Biologists used the lab information to infer hazards to fish due to exposure of CECs.

So far, lab studies are confirming that many of the CECs have negative impacts on fish including mortality, developmental effects, and reduced reproductive capacity. Many studies have also confirmed that some CECs accumulate in fish.

Tumor on the mouth of a bullhead – Photo Credit Jo Ann Banda, USFWS.

What does it mean when other animals–or even people–eat those fish?

Not enough information is known yet to say for sure how eating fish living in a CEC rich environment could impact humans, but a study published in 2015 evaluated a large group of northeastern bats to determine if CECs could be found within those bat populations.

Have you ever heard of the phrase “you are what you eat”? That’s essentially what’s happening here.

Northeastern bats have a high metabolism, meaning they have to eat a lot of food! The bats are eating bugs, which may have lived in contaminated environments. In turn, eating a lot of insects could mean they have a higher likelihood of exposure to chemicals in the environment. The bugs are incorporating the contaminants into themselves from eating or living with exposure to these contaminants, and when the bats eat the bugs, the contaminants within the bugs are being incorporated into bat tissues.

The results of the 2015 study showed that CECs could be detected within the bats themselves. The CECs detected most frequently in samples were PBDEs (compounds used in flame retardants), salicylic acid, thiabendazole(a fungicide), and caffeine. Other compounds detected in at least 15% of bat samples were digoxigenin, ibuprofen, warfarin, penicillin V, testosterone, and N,N-diethyl-meta-toluamide (DEET), all of which are commonly used.

How do these contaminants make their way to bats? Well, we have some clues. When we dispose of household or personal items, or apply substances to our properties, they can make their way to streams. Insects accumulate them because they live in those areas, and then the bats feed on the insects.

Many of the CECs we are most concerned about were made to be biologically active in the human body (i.e. medications) and we know they work well because they made it into the marketplace. That information coupled with the fact that we know very little about the broader scope of CECs, besides lab studies, is troubling.

What this means for human health….we don’t know. A large number of people get their drinking water from the Great Lakes. Emerging contaminants have been found in some Great Lakes drinking water supplies.

These are complicated issues that warrant deeper exploration to determine the potential human and environmental health impacts as well as ways to help prevent the continued contamination of our environment.

We live in a world where these types of far-reaching health concerns have become prominent in our day to day lives. It is a stark reminder of the finite resources our world possesses and that the actions we take greatly impact not only our direct health and well-being, but the global health of all who inhabit the earth.

Traditional Knowledge of Penobscot Indian Nation Influence on Wildlife Projects

This blog is the third in a series written by Jr. Native American Liaison Zintkala Eiring to highlight our Tribal partners and the work they are doing to manage wildlife populations – in honor of National Native American Heritage Month.  

For centuries, Tribal members from the Penobscot Indian Nation trapped, hunted, fished, and collected their food throughout their Tribal lands in what is current-day Maine. They passed along their knowledge to their children about when the salmon returned to the Penobscot River, where otter lived and nested along the islands, and how to collect fiddlehead fern at the right time. This traditional ecological knowledge was passed down from generation to generation – and is now used as important information to bolster scientific research about native wildlife and plants.

So, when Tribal members began experiencing changes in wildlife populations, they knew something was wrong.  Kristin Peet, wildlife biologist for the Penobscot Indian Nation, began researching the fur-bearing mammals in the Penobscot River, including otters, muskrats, and mink. In the past decades, Penobscot Indian Nation Tribal members of Maine experienced declines in the local otter population. Oral histories passed down through the Penobscot people describe ancient sites of otters that aren’t in existence anymore. The decline of known otter sites meant fewer opportunities for Tribal people to practice traditional trapping on the Penobscot River for subsistence. When Peet began her research on the otter population, she predicted the otter would be a prime environmental indicator of the health of the Penobscot River and its inhabitants. Combining the traditional ecological knowledge of the local Penobscot people, their account of the decline of otters, and Peet’s studies, they found that there are new otter sites which suggests a change in habitat preferences by the otter population.

However, the otter is not the only traditional food of the Penobscot Indian Nation and there was more to be known about other native wildlife impacts on the Penobscot River. Peet listened to the traditional knowledge of tribal members who relayed changes in their harvesting practices on traditional plants and fishing habitats, as well. Tribal members believed there were contaminants in Penobscot homelands from the Lincoln Pulp and Paper Mill, which used to lie upstream of Indian Island, one of the two-hundred Islands of Penobscot Indian Nation territory. Many Tribal members were worried that all harvestable items were contaminated downstream of the papermill. Thus, tribal members began to travel further north to harvest fiddleheads ferns and flagroot, a traditional medicine to the Penobscot people.

To determine whether contaminants were present in the Penobscot River, Peet and the Water Quality Program of Penobscot Indian Nation, University of Connecticut, and Maine Department of Inland Fisheries and Wildlife began testing muskrat, mink, and otter for contaminants like PCB’s. These three species were collected from traditional Tribal and non-Tribal trappers and provided the team opportunities to sample for contaminants. The muskrat, a herbivore, had relatively low-concentrations of contaminants, but had high traces in the liver. The mink, a predator, had high contaminants of PCB in their muscles. The otters’ contamination levels varied from little to no presence.

Muskrat, a sustenance food to the Penobscot people. In tradition, Penobscot elders eat the brain of the animal. The muskrat pictured here is from Seedskadee National Wildlife Refuge. Photo Credit: Tom Koerner/USFWS.

Using these findings, Peet and her team produced a culturally relevant brochure for Tribal members and schools. It is entitled “Wild Food Safety Series” and explains the traditional diet of fish, plants, and wildlife. It includes “do, don’t, and why” for traditional diets, how to culturally and sustainably harvest, and the recommended consumption rate for animals that have contaminant levels. For example, the brochure states individuals can “eat up to 10-ounces of brook trout and landlocked salmon from Penobscot nation waters per week” to help inform Tribal members in how they can practice their traditional subsistence practices safely.

In the future, a “wild foods safety” brochure series be will available and will include other fish, wildlife and plants.

Once the wild food safety series is provided for plants and wildlife, Tribal members will know the healthy sustenance rate for muskrat, otter, mink, fiddlehead, and flagroot. In fact, Tribal community members will no longer have to travel North of the old papermill for fiddlerroot because the study showed it is healthy anywhere in Penobscot Tribal Trust lands, even downstream of the old papermill.

Fiddlehead captured by USFWS

The wild food safety brochures increase Tribal members’ accessibility to traditional foods and furthers the practices of trapping and harvesting that are passed down from generation to generation in Penobscot culture. And it is all thanks to the traditional ecological knowledge passed down from Penobscot people.

The Furbearers Contaminant Study was made possible by the dedication and efforts of the Penobscot Indian Nation and the Tribal Wildlife Grant program of the U.S. Fish and Wildlife Service. Grants are funded through an annual appropriation from the Land and Water Conservation Fund. For more information about tribal wildlife grants please visit https://www.fws.gov/northeast/nativeamerican/index.html