Group

Intertidal Crabs

Research Questions: How do populations of Asian shore, European green, and native crabs compare up and down the coast of the Gulf of Maine? Are crab populations changing over time and in response to warming temperatures? Where will Asian shore, European green, and native crabs be most abundant in the future?

Why this matters

Invasive crabs are ravaging intertidal zones across the Gulf of Maine. We need more data to understand how these populations are changing and where they could have the greatest impact in the future.

Partner
  • Manomet
Season

All

Intertidal Crabs

Protocol Overview

  1. Find a date, time, and place to collect your data. Select a rocky intertidal field site, and choose a date and time to collect data that is within one hour of low tide.
  2. Lay a transect, or measuring tape, parallel to the water line, as close to the water as possible.
  3. Use a random number generator or deck of cards to find a random location along the transect to place your quadrat.
  4. Thoroughly search your quadrat for crabs. Place found crabs in a bucket to sort later.
  5. ID, sort, measure, and sex the crabs crabs in your bucket, recording your findings on your datasheet.
  6. Collect photo evidence to support your findings.
  7. Return native crabs to the quadrat. Return or dispose of invasive crabs.

Resources:

Project Owners

Marissa

Marissa McMahan

Manomet

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Elizabeth

Elizabeth Stephenson

New England Aquarium

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Project Partners

Manomet