Freshwater Mussels in Massachusetts: Ecology and Conservation of an Imperiled Fauna

Jason R. Carmignani, Ph.D.Aquatic Ecologist

MA Natural Heritage & Endangered Species Programjason.carmignani@mass.gov

Who am I?• Graduate work all in Massachusetts

– Bridle Shiner (MESA-listed)

– Winter water level drawdowns in MA lakes

• Joined NHESP – MassWildlife Nov. 2019

• Monitor state-listed and uncommon mussels (6), dragonflies/damselflies (22), snails (5), crustaceans (7), fish (10)

WHAT IS A FRESHWATER MUSSEL?

What is a Freshwater Mussel?

• Phylum – Mollusca

• Class – Bivalvia

• Order Unionoida

– Margaritiferidae

– Unionidae

• Is it a Mussel or a Clam?

What is a Freshwater Mussel?Zebra Mussel - Invasive

Asian Clam - Invasive

Fingernail Clam - Native

Other Freshwater bivalves in North America are in the order Veneroida

More closely related to marine clams

HOW MANY SPECIES ARE THERE?

Mussel Diversity in North America

~ 300-320 Species

Mussel Diversity in Massachusetts

12 Species (~ 3.5 %)

Mussel Diversity in Massachusetts

Archambault et al. 2018 Biodiversity Research

Freshwater Mussels in MA

• 12 species

• 6 listed under MESA

• 10 species in MA State Wildlife Action Plan

• 1 Federally Endangered – Dwarf Wedgemussel

Eastern Pearlshell

Dwarf Wedgemussel

Eastern PondmusselTidewater Mucket Brook Floater

Eastern Lampmussel Yellow Lampmussel Eastern Floater

Eastern Elliptio

Glochidialarvae

Adultmussel

Fish host

Juvenilemussels

FW Mussel Life Cycle

Metamorphosis

A. Fritts

Fish-host Attraction Strategies

• Large Mantle Lures - Carnivorous Fish

• External Lures – Carnivorous Fish

• Diminutive Lures – Insectivorous Fish

• Broadcasters – Host Generalists

• Trappers – Few species – all use Darters

• Maternal Sacrifice – one known species – FW Drum as host

Used by Mussels in Massachusetts

M. C .Barnhart

Mantle Lures

M. C .Barnhart

Mantle Lures

Mantle Lures

Broadcasters

Creeper

Broadcasters

Eastern Floater

M.C. BarnhartM.C. Barnhart

Important Conservation Targets

• Susceptible faunal group– North America: >70%

imperilment rate

– In MA: 10/12 species that require conservation action

• Important role in ecosystem– Improve water quality

– Nutrient cycling and energy transfer

– Create habitat for inverts and fish

• Habitat loss and degradation – Flow and sediment alteration

– Population isolation via physical barriers

• Invasive species – zebra mussels, Asian clams

• Contaminants

• Climate change

• Species biology: long-lived, sedentary.

→Populations less resilient to future changes

Threats to Mussels

Conservation and Restoration Actions

• Ecological research

• Population monitoring

• Watershed land protection

• Improved habitat connectivity

• Translocation

• Propagation

• Reintroduction

Benefits

• Increase stream connectivity

• Restore natural hydrology/geomorphology

• Supportive of native fish communities

Challenges

Mussels susceptible to:

– Dewatering

– Burial by sediments

– Changes in food availability

Dam Removal & Mussels

• Millie Turner Dam Removal – completed• Sucker Brook Dam Removal – 2021

Can we overcome challenges of dam removal?

• Alter dam removal process

• Manage mussels through translocation efforts

• Do long-term benefits outweigh costs?

– Increased host-fish?

– Habitat improvement?

• Pepperrell, MA

• Nissitissit River, Nashua River Watershed

• Removed in Fall 2015

• Most of land upstream owned by MassWildlife

• Important Mussel Community

– 2 MESA listed

– 2 State Wildlife Action Plan (SWAP) list species

– 1 Common species

Alex Hackman, MA DER

Millie Turner Dam

Peter D. Hazelton

Brook Floater: A High Priority Species

Brook Floater – State Endangered• Petitioned for Federal

Listing

• 4 populations in Massachusetts

• Threats:

– Habitat fragmentation

– Small population sizes

Other Species Involved

Creeper – Special Concern Triangle Floater - SWAP

Other Species Involved

Eastern Pearlshell - SWAP Eastern Elliptio - Common

Turner Dam

Millie Turner Dam Removal

• Habitat surveys – June-August 2015

– Up & downstream of dam

• Translocation– Started July 2015

– Moved out of dam influenced habitat

– ALL MUSSELS TAGGED

• Final translocations– During dam removal

• Headcut of river impeded by an old dam

Higher Abundances

Sparse

Long-Term Monitoring

• Documented habitat change post-dam removal

• Identified species-habitat relationships

• Monitoring population status (2018-2020)

– Growth, population size, mortality

• Analysis and results to come!

What was accomplished?

• > 200 Target mussels translocated– 50% were State Listed

Species

• > 25 Volunteers– >150 volunteer hours

• Baseline habitat and population data – Management plan

development– Inform decisions on future

dam removals

Sucker Brook Dam Removal

• Proposed for late summer/fall 2021

• Smaller-scale than Millie Turner

Sucker Brook Dam Removal

• Will translocate 2 state-listed and 1 SWAP species

• Measure impact of small dam removals Eastern Pearlshell, Eastern Elliptio

Future dam removals

• Squannacook River?– Creeper (SC), Triangle Floater, Alewife Floater,

Eastern Elliptio, Eastern Pearlshell

• Rare and sensitive taxa a priority

• Similar level of effort as Millie Turner Dam?– Mussel species abundance and composition

– Impact of dam removal on geomorphic habitat

Watershed Land Protection

• Protected land (in MA):

– Nissitissit Watershed

• 12.8% of total watershed area

• 40.1% is DFG wildlife management area

– Squannacook/Willard Watershed

• 17.8% of total watershed area

• 35.8% is DFG wildlife management area

Protection of In-stream Habitat

• Large wood = geomorphic/habitat complexity

• Management of beaver dams

• Mussel habitat restoration?

Propagation & Reintroduction

• Partners with researchers at USGS Coop Unit at UMass, USFWS - Cronin Aquatic Resource Center, North Attleborough National Fish Hatchery

• Brook Floater and Yellow Lampmussel

• Identify suitable habitat

• Establish new populations to increase resiliency in Massachusetts

Research and Restoration Needs

36

• Increased knowledge of distribution and abundance– NHESP surveys

• Identification of threats to most sensitive populations

• Identification of restoration potential– Available habitat– Propagation and restoration

feasibility

Creeper – Special Concern

Brook Floater - Endangered

Where to Learn More

Websites• Unio Gallery – Dr. Chris Barnhart

– unionid.missouristate.edu

• Freshwater Mollusk Conservation Society – FMCS– Molluskconservation.org

• MassWildlife Factsheets – (10/12 species)

– Found in the State Wildlife Action Plan

Where to Learn MoreFreshwater Mussels and the Connecticut River – Ethan Nedeau & Conn. River Conservancy

Immersion: the Science and Mystery of Freshwater Mussels – Abbie Gascho Landis

Questions?