Friday, August 20, 2021

Tracking Brook Trout

        At Breakheart Brook in the Arcadia Management Area in Exeter, Ellie Madigan bushwhacks along the edge of the stream carrying a hand-held antenna and receiver to listen for an electronic beep that indicates a brook trout is nearby. During a half-mile of walking, she hears only the sounds of the gurgling brook, a few songbirds, and the buzzing of insects. So she heads in the opposite direction.
        Madigan, a University of Rhode Island student, is joined in the search by fellow student Mitchell Parizek and Corey Pelletier, a biologist with the Rhode Island Department of Environmental
DEM biologist Corey Pelletier and URI students (M. Derr)
Management, who devised the research project to track the movement of the state’s only native trout species. After capturing 75 trout in May and implanting a tracking device in each of them, Pelletier, Madigan and Parizek are trying to relocate each of the fish every week throughout the summer to figure out where the fish go as water temperatures rise.
        “One of the things brook trout need for survival is cool water during the summer and high levels of dissolved oxygen,” said Pelletier. “That dictates the habitats they can spend time in and survive in. But often there are significant numbers of impoundments — dams dating to pre-industrial times that not only inhibit trout movement but also warm up the water.
        “One reason why we find brook trout in these small streams is because the streams are often fed by groundwater — whether through seeps in the woods or seeps that come through the streambed — and groundwater is cool and contains enough oxygen,” he added.
        Most of the state’s small number of brook trout are found in the Wood-Pawcatuck watershed in South County, so that’s where Pelletier and his team are spending most of their time.
        Brook trout are considered “a species of greatest conservation need” in Rhode Island. They typically grow no larger than 12 inches, and often only 6 to 8 inches, because their limited habitat in small streams keeps them from growing larger. The chief threats they face are changing environmental conditions – mostly warming waters and low dissolved oxygen – as well as pollutants due to run-off from nearby developments. Stocked trout are also a concern, since they are usually non-native species that are larger than brook trout and can outcompete the native species for food and habitat.
        That’s why the state will no longer be stocking trout in the Beaver River, and fishing there will be limited to catch-and-release only to create a stream specifically managed for wild brook trout. Last year the state also increased the minimum size of trout that can be harvested in Rhode Island waters to eight inches, which means that most brook trout will have to be released if caught.
        Charlestown resident Jim Turek supports these efforts to protect brook trout and their habitat. An enthusiastic trout fisherman who has little interest in catching stocked trout, he calls brook trout an iconic species for New England.
        “They’ve always been here, and they’ve sustained local communities for centuries as a source of food and enjoyment,” he said. “It’s a heritage fish that looks better and tastes better than trout grown on food pellets in a hatchery.”
        Turek is one of dozens of Rhode Island trout fishermen who are committed to protecting the species and who are strict about not revealing the location of their favorite trout streams.
        “We believe we should do all we can to save these fish,” he said. “Brook trout populations are so small that if we tell the public where to go fish for them, they’ll remove some of the bigger ones and we won’t have a sustainable population any more. We’re happy to just walk along a stream and see a beautiful fish and know they’re still there. We don’t even need to catch them.”
        Even among the fishermen there is disagreement, mostly about the most appropriate fishing method for catching brook trout. The fly fishermen say that using flies is less likely to cause injuries to the fish that could lead to their death, enabling the fish to be released unharmed. The bait fishermen disagree.
        Pelletier isn’t taking sides. He’s mostly interested in learning as much as he can about where the trout go in summer so those areas can be protected from development and fishing pressure and to figure out how to keep the water temperature in those locations from getting too high.
        “The optimal water temperature for brook trout is 12 to 18 degrees Celsius, because that’s when they exhibit their highest growth rate, but above 18 you get into stressful conditions for them,” Pelletier said. “Above 23 and they don’t exhibit positive growth, and above 25 is potentially lethal, but it depends on how long they’re exposed to those temperatures.”
        His tracking study ran into difficulties immediately after the tagged fish were released in May because a stretch of hot weather in early June forced the fish to move much farther than Pelletier expected.
        “Wherever they were in May is now too warm for them, so they’ve had to go somewhere else,” he said. “But it seems like when temperatures are suitable, they can remain in the same spot for weeks.”
        Back at Breakheart Brook, the research team found just two tagged brook trout by the end of a long day of tracking. But they weren’t discouraged. They had many more miles of shaded streams to search to find the heart of the brook trout’s summer range.
        “The information that comes out of this study will be very important for the future management of this species,” Pelletier said. “We’ll understand the areas necessary to support trout through the very stressful high-temperature periods. It’s going to give us insight into management actions we can take to further protect the species.”

        This article first appeared in the August 2021 issue of South County Life magazine.

Monday, August 16, 2021

Thanks to rain, it's been a mushroom summer

        The incredible volume of rain that was dumped on southern New England last month has made for an unusual summer.
        While the drought-stricken southwestern United States is no-doubt jealous of our abundant precipitation, I’m not so thrilled with it. All that rain has made my weedy lawn grow so fast that I can’t mow it fast enough. It has also accelerated roadway runoff into local water bodies, increasing levels of pollutants in ponds and streams and leading to more algae blooms than usual.
         On the other hand, the rain has made it a banner year for mushrooms. During a five-minute walk around my yard last month, I counted more than 90 mushrooms of 11 different species. While I admit that I don't know a great deal about mushrooms, I know enough not to pick and eat any of them, since
Chestnut bolete (Todd McLeish)
many can be deadly and most are notoriously difficult to identify. And yet they are intriguing for their beautiful colors and forms, and they are vitally important to the health of trees and forests.
        I just love how some mushrooms look like coral and others like mounds of jelly; some are round puffballs and others like tiny parasols; some look like giant pancakes while others remind me of tree rings. In my yard alone, I’ve seen them in red, purple, yellow, white, brown and orange. And some even have bioluminescent qualities. Shine a black light around your yard at night and some of your mushrooms will probably glow in the dark.
        Strangely enough, those biology lessons in high school that probably instructed you that every living thing is either a plant or animal were wrong. Mushrooms don’t fall into either category. They belong to their own kingdom because, among other reasons, they differ from plants and animals in the way that they obtain their nutrients. Unlike plants, which use photosynthesis, and animals, which consume their food internally, mushrooms grow into and around their food source and digest it externally.
        The mushroom we see at the surface is only a tiny part of the entire organism, however. Simply put, the mushroom is the reproductive part of a fungi, sort of like the fruit of a plant. Once the mushroom distributes its spores, it melts away, but the rest of the fungal organism lives on, often for many years.
        Here’s another high school biology lesson that wasn’t entirely accurate – trees in the forest don’t actually take up water and nutrients through their roots. The underground part of mushrooms is responsible for that job. Healthy forests are dependent on hundreds of thousands of miles of fungal threads called hyphae to gather water and nutrients and supply it to the tree’s roots. (Some scientists say that these hyphae make up 90 percent of the life living in our soils.) In return, the trees give the fungus sugars they produce in their leaves. Without this symbiotic relationship – called mycorrhizae – our forests would cease to exist as we know them.
        But that’s not all we get from mushrooms and fungi. They are an important source of pharmaceutical compounds, too, and they have the unique ability to penetrate hard wood and biodegrade it. Yeast fungi also play a key role in the production of bread and wine, which puts them high on my list of the world’s most important organisms.
        All this, and mushrooms taste good, too. I only wish we didn’t have to get flooded out of our homes to see so many of them.

        This article first appeared in the Independent on Aug. 14, 2021.

Friday, August 13, 2021

Soggy July was good and bad for wildlife, environment

        Rhode Island experienced the third-rainiest July on record, with most areas receiving more than twice the average monthly precipitation and some areas receiving much more, especially in the northwest corner of the state. Local scientists said all that rain likely had an impact on wildlife and the environment, in both positive and negative ways.
        In many neighborhoods, it was the mushrooms that were the most visible winners. Mushrooms of numerous species sprouted from lawns, gardens, forests, meadows and elsewhere in huge numbers. Abundant rainfall brings to life the underground portion of a fungi — called the mycelium — resulting in the production of mushrooms, according to Ryan Bouchard, founder of the Rhode Island-based Mushroom Hunting Foundation.
        “You end up with larger flushes of mushrooms, species not normally seen in such abundance, and
Jackson's slender amanita (Ryan Bouchard)

species seen in uncharacteristic size,” he said. “This wasn’t just an extra rainy July, though. It was a comeback from the prolonged terrible mushroom season of 2020 when we had a lack of rain throughout the year that left the mycelium mostly dormant and weakened.”
        The near-daily July rains provided what Bouchard called “a kick in the pants to the mycelia to get back into action.” He said it was an especially good month for Jackson’s slender amanita, a brightly colored edible mushroom that is usually hard to find but which was abundant in many places in July. Black trumpet mushrooms and chantarelles also had a major comeback following a year in which Bouchard saw only one.
        Other wildlife didn’t fare nearly as well as the mushrooms, however. Butterflies, moths and dragonflies were barely noticed in many areas for much of the month, though that doesn’t mean the insects were killed by the rain. Most were probably just in hiding. They are typically visible only during sunny days, and since July had few sunny days, most species did not make their presence known.
        Butterflies and moths in their caterpillar stages, though, may have succumbed due to the rain. Martin Wencek, a butterfly expert and a supervisor in the Freshwater Wetlands Division of the Rhode Island Department of Environmental Management, said any insect that goes through a caterpillar stage faces high mortality during especially wet years.
        “The dampness can promote bacterial growth that does them in effectively,” he said.
        An isolated month of extreme rain isn’t likely to have a serious impact on dragonflies, said Virginia Brown, author of Dragonflies and Damselflies of Rhode Island. But if torrential rains result in dam breaches, it could affect dragonfly populations and their habitats.
        “The problem from an odonate [dragonfly and damselfly] perspective is that when a dam breaches, the water it holds back — usually in the form of a pond or reservoir — is released downstream and, poof, there goes the pond habitat and all the aquatic critters like eggs and larvae in the water,” Brown said. “The pond becomes a stream channel, and then the hydrology and vegetation change.”
        Brown believes several populations of rare damselflies disappeared from the Ocean State in just this way as a result of the floods of March 2010.
        On the other hand, she said, “all this rain will probably result in high mosquito populations, which will mean more food for odonates.”
        More mosquitoes means more food for insect-eating birds as well. But since the rains occurred during the peak of bird nesting season, it may have negatively affected the ability of some birds to fledge their young successfully. According to Steven Reinert, an ornithologist who monitors the nests of one of Rhode Island’s most-imperiled birds in a marsh on the Bristol/Warren line, when heavy rains coincide with extreme high tides in salt marshes in mid-summer, saltmarsh sparrow nests can become flooded.
        “Rains coinciding with flooding events not only raises the elevation of the floodwaters, but also keeps water levels at or near nest level for longer periods of time,” he said. “Thus, the extensive rain of July likely cost the lives of nestling saltmarsh sparrows at Jacob's Point, but the extent of damage is impossible to quantify.”
        The abundant precipitation provided a significant boost to lawns and wild plants, but many cultivated plants, especially vegetables, struggled to survive. Heather Faubert, who directs the Plant Protection Clinic at the University of Rhode Island, said the rains led to significant impacts on tomatoes, peppers, onions, carrots, squash and other varieties from foliar diseases. Many fruiting shrubs were affected by pest insects as well.
        “Spotted-wing drosophila [a nonnative fruit fly] love high humidity, so they are doing great infesting blueberries, blackberries and raspberries,” Faubert said.
        Water quality in area lakes, ponds and streams was likely affected by the abundant rainfall, too, but not always in the same way. Elizabeth Herron of the URI Watershed Watch program said some lakes and ponds receive contamination from stormwater runoff, while others that are already contaminated may be improved by having stormwater flush out the contaminated water.
        “Increased runoff does mean we are seeing higher levels of bacteria in many of our sites, even in rural areas, after rainfall events,” she said. “We are also seeing some increased staining in our lakes and ponds due to water being flushed out of wetlands. Tannic acids often color the water like tea or even coffee. The darker stained water reduces water clarity and may impact algal and plant growth. In some places that can be a good thing, in other places that reduces productivity, potentially limiting growth of fish, zooplankton and other critters.
        “In other words, it is all very complicated. But ultimately I would argue that having more water in July is preferable for water quality than drought.”

        This article first appeared on EcoRI.org on August 9, 2021.