Restoring Kejimkujik National Park Seaside

What’s the issue?

Two crabs, the lower one smaller and greenish, held up for display.
Since removing European green crab (top) from estuaries, we’ve seen an increase in native species, like rock crab (bottom). Photo: © Gabrielle Beaulieu

In the 1980s, ships leaving Europe and North Africa inadvertently brought European green crabs to the Eastern U.S., where this invasive species began to flourish. Eventually, the crabs migrated north, thriving in the turquoise waters of Kejimkujik Seaside. There they began to severely affect the marine ecosystem – destroying eelgrass meadows while searching for food and voraciously consuming juvenile soft-shell clams. Both eelgrass and soft-shell clams are important parts of Kejimkujik Seaside estuaries; eelgrass meadows form nursery habitats for juvenile fish and invertebrates, while soft-shell clams regulate water quality and are a critical food source for migrating shorebirds. At its peak, the green crab invasion reduced eelgrass down to 2 percent of its previous extent and juvenile soft-shell clams became exceedingly rare. Faced with this alien threat, Parks Canada is determined to act before green crabs cause irreversible damage to Kejimkujik Seaside.

What’s our approach?

  • Design a pilot project in consultation with local fishers and coastal ecosystem experts to develop and test an effective European green crab trap.
  • Remove as many green crabs as possible and measure effectiveness by monitoring the recovery of eelgrass and soft-shell clam populations.
  • Refine and expand trapping effort and eelgrass restoration in two lagoons.
  • Develop an engaging visitor experience.

What’s been accomplished?

  • Designed and tested an effective green crab trap in 2010, halting the loss of eelgrass within the first season.
  • Building on the early trapping success, initiated the Coastal Restoration Project in 2014, removing over 2 million crabs.
  • Recovered 38 percent of eelgrass beds by replanting in crab-free areas.
  • Increased the number of juvenile soft-shell clams and the overall health of the population.
  • Witnessed the recovery of native crab, fish and bird populations to the estuaries.
  • Launched the successful Gone Crabbin’ visitor experience, promoted the project with regional news media, and encouraged 2,000 hours of volunteer time for coastal restoration efforts.