FLEXING FRESHWATER MUSSELS 16 — Peter Hazelton TIGHT-KNIT GRASSLANDS 20 — Karro Frost, Robert Wernerehl by the NUMBERS 24 — Sarah Maier, Caitlin Sawicki

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FLEXING FRESHWATER MUSSELS 16 — Peter Hazelton TIGHT-KNIT GRASSLANDS 20 — Karro Frost, Robert Wernerehl by the NUMBERS 24 — Sarah Maier, Caitlin Sawicki No. 3, 2020 $3.00 Massachusetts Endangered Species Act 43 4 Vol. 70 No. 3 FEATURES EDITORIAL: THREE DECADES OF MESA 2 — Mark S. Tisa LOOKING BACK, MOVING FORWARD 4 — Everose Schlüter, Thomas French Photo courtesy MassWildlife Archives LISTING A SPECIES: WHY AND HOW? 10 12 — Michael W. Nelson PEREGRINE PRIDE 12 — David Paulson, Andrew Vitz FLEXING FRESHWATER MUSSELS 16 — Peter Hazelton TIGHT-KNIT GRASSLANDS 20 — Karro Frost, Robert Wernerehl BY THE NUMBERS 24 — Sarah Maier, Caitlin Sawicki Photo © Charlie Tadeu LANDSCAPE-SCALE CONSERVATION 26 26 — Michael W. Nelson, Chris Buelow WOOD TURTLE PARTNERSHIPS 32 — Michael T. Jones DEMYSTIFYING THE EASTERN SPADEFOOT 36 — Jacob E. Kubel HOW YOU CAN HELP! 40 On the Cover: There is perhaps no greater reminder of the vulnerability of species listed under the Massachusetts Endangered Species Act (MESA) and the great progress MassWildlife has made over the past 30 years under Photo by Chris Buelow/MassWildlife MESA than this recently hatched, ground-nesting seabird 36 facing the dawn of a new day on a Bay State beach. This Least Tern (Sternula antillarum, Special Concern) is the smallest of our four breeding tern species. You can hear its squeak-toy calls on the sparsely vegetated coastal beaches where it nests. Photo © Dean Cerrati TO SUBSCRIBE OR BUY A GIFT SUBSCRIPTION PLEASE VISIT mass.gov/dfw/magazine OR CALL (617 ) 626-1590 ANY WEEKDAY Questions about your subscription? Change of address? Photo © Carol Entin Call toll free: (800) 289-4778 FLEXING FRESHWATER MUSSELS he Brook Floater (Alasmidonta varicosa, Endangered) may not be Tamong the most charismatic ani- mals on the Massachusetts Endangered Species Act (MESA) list. This freshwater mussel only grows to about three inches long and could easily be mistaken by Photo © Ayla Skorupa the casual observer as one of the rocks surrounding it on the streambed. Nev- ertheless, this state-listed species has found itself at the center of research and conservation partnerships in Massa- chusetts and wherever this mussel lives in North America. Work conducted by MassWildlife to protect and restore Brook Floater is an example of how we use scien- tific research, targeted management and restoration, and critical collaborations to A Brook Floater filtering stream water. protect both endangered and common the food web for stream fish. In return, species throughout the Commonwealth. the mussels rely on the fish to reproduce. Despite its unassuming appearance, All native mussels in the state have new populations of the Brook Floater and parasitic larvae (called glochidia) that information about its biology are sought undergo metamorphosis on the gills or by conservation biologists throughout fins of fish. These baby mussels typically the species’ range from New Brunswick, don’t harm the fish but catch a free ride to Canada, south to Georgia. In Massachu- new areas of the waterway to start their setts, the Brook Floater is one of three life on the riverbed. Some relationships freshwater mussels listed as Endangered between mussels and their host fish are under MESA and was recently reviewed so specific that a single mussel species for listing under the federal Endangered may only use a few different species of Species Act. Once common in cool fish as hosts. Brook Floater on the other freshwater streams and rivers along hand may use more than 13 fish species the Atlantic coast, the Brook Floater’s as hosts. populations are now found only in small Recent management, restoration, and isolated remnants of its historical range. research efforts to preserve the remain- The Brook Floater and the native fishes ing four populations of Brook Floater in that share the same habitat are inextri- the Commonwealth further demonstrate cably linked. Like all native freshwater the need for environmental partnerships mussels, the Brook Floater is a filter within and across states. MassWildlife feeder that removes algae and bacteria has fostered strong partnerships across from streams, thereby improving water the Brook Floater’s range, including here quality and concentrating nutrients. at home, to better ensure the persistence These actions provide the foundation of of this mussel into the future. by Peter Hazelton 1616 Photo © Ayla Skorupa Jason Carmignani, Aquatic Ecologist for MassWildlife’s NHESP, digs for buried mussels in the Nissitissit River. MassWildlife has been monitoring the changes to mussel habitat following the removal of the Millie Turner Dam in 2015. Ecological Restoration removal was to restore connectivity for migrating river herring and other native Benefits Rare Species and freshwater fishes, and to increase habitat Recreational Fisheries for Brook Floater and four other freshwa- Among the greatest threats to freshwa- ter mussels found in the river. Despite ter mussels and our native fishes is the immediate recognizable benefits to the fragmentation of habitats by dams. The fish community, MassWildlife was faced majority of dams in the Commonwealth with the challenge of offsetting immedi- are historical and have no current use for ate habitat changes and the possibility power generation. These structures can of losing some of the mussels versus the be barriers to fish and mussel migration possible long-term benefits of increased between suitable habitats along the river. habitat for Brook Floater. To ensure that In some cases, dams are the major cause Brook Floater were not harmed during the of declines in diadromous fishes like removal process, MassWildlife’s Natural Alewife, Blueback Herring, and American Heritage & Endangered Species Program Shad that migrate between freshwater (NHESP) enlisted the help of volunteers and the ocean for breeding. Dams also and partners to scour the river to find limit movements of fish that stay in riv- rare mussels and carefully relocate them ers throughout their lives, and further to stable habitats away from the short- alter river habitat by limiting the natural term changes following dam removal. In erosion and accretion of sediments. On all, partners translocated over 200 rare the other hand, dams can provide some freshwater mussels—nearly half of which stabilization of local habitats that are were Brook Floater. beneficial to freshwater mussels, and Following the dam removal, NHESP has the act of removing a dam could result continued to monitor Brook Floater and in an immediate loss of habitat for some other mussels relocated on the Nissitissit animals. River. NHESP has also monitored changes In 2015, MassWildlife worked with state, to the habitat immediately above and federal, and local partners to remove below the dam removal site, and initial the Millie Turner Dam on the Nissitissit results indicate that the dam removal will River in Pepperell. The goal of the dam create more habitat for Brook Floater. 17 MassWildlife employs scientific research Group, consisting of cooperators from and monitoring in cases like this to better fish and wildlife conservation agencies understand the impact and benefit of from 15 states, two federal agencies, management actions. By understanding colleges and universities, and environ- how Brook Floater and other mussels mental consulting groups. respond to the dam removal and translo- cation, MassWildlife can alter approach- Partners of the Brook Floater Working es to provide better conservation and Group have worked diligently over the management of mussels during future past four years to develop standard dam removals. survey methods that can be used to map the extent of Brook Floater populations The Nissitissit River and its tributar- throughout its range. By developing ies are home to exemplary wild and shared survey protocols, the working stocked trout fisheries in MassWildlife’s group is able to more clearly compare Northeast District. MassWildlife’s collab- data collected in different states and orations with the Division of Ecological better identify the Brook Floater’s habitat Restoration, the Squan-a-Tissit Chapter needs. Previously, researchers in differ- of Trout Unlimited, and the town of Pep- ent states or regions were using different perell to improve fish passage on the survey methods, and the resulting data Nissitissit River, Gulf Brook, and Sucker were not comparable. Moreover, by incor- Brook will benefit these fisheries. Trout porating updated scientific approaches are not the only beneficiaries of these and standard survey methods, it will be restoration efforts. The habitat of sev- easier to track the status of the species eral MESA-listed species within these across its broad range and make con- tributaries and the federally designated servation plans at scales beyond state Wild and Scenic portion of the Nissitissit boundaries. River will benefit from increased stream continuity and restored river reaches. Habitat data collected throughout the The Millie Turner Dam removal project Brook Floater’s range help scientists and highlights that ecological restoration managers identify new areas to search can serve to benefit many native rare for unknown populations of Brook Floater species, but also benefits recreational and to find potential areas for habitat opportunities for anglers. Such projects restoration or reintroductions. The Brook would not be possible without strong Floater Working Group has used mussel partners and close coordination among data to develop predictive models of MassWildlife staff. potential habitat using a network of river data in a geographic information system. Coordinated Research and The resulting predictions do not show us
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