Celebrating Citizen Science Month

Helping Hands for Horseshoe Crabs

Horseshoe crabs are an important part of our coastal ecosystem. Their eggs feed migratory shorebirds and other wildlife all along the Atlantic Coast—females can lay up to 100,000 at a time! Unfortunately, overharvesting of horseshoe crabs and habitat degradation has left us with fewer horseshoe crabs and not enough eggs for shorebirds, fish, and terrapins (a species of turtle).

Lend a helping hand to horseshoe crabs in need by heading to a calm, sandy beach during late spring and early summer and flipping over any crabs you find upside down (legs up). If you find them with wet feet and shells up, they are probably spawning and should be left alone—count how many you find on your beach and let us know what you find! You can also see if you can spot the difference between males and females: males are small and attach to females, and females are larger because they carry the eggs.

Originating roughly over 450 million years ago, horseshoe crabs are considered living fossils.

Tracking Invaders

The European green crab is an invasive species that was transported to the United States in ship ballast water in 1817. In recent years, they have rapidly increased in abundance in the Gulf of Maine as ocean temperatures have warmed. Unfortunately, they like to eat native species such as soft-shell clams and mussels, leading to declines in their populations and negative impacts to the fishermen whose livelihoods depend on those species. Manomet has been working to create a fishery for green crabs, which would help fishermen to benefit from them and would promote removing them from the environment.

You can find green crabs on most shorelines in New England that have moveable rocks and seaweed. Simply flip over rocks or gently move aside seaweed to find them! When you find one, see if you can determine if it’s male or female, gently squeeze it to see if it’s hard or soft (indicating if it has recently shed its shell in order to grow), count how many claws and how many legs it has to determine if it’s injured (the maximum a crab can have is 2 claws and 8 legs), and note the color (green crabs can range from gray-green to orange-red in color). Head out to your local coastline and report your findings to Marissa McMahan, Fisheries Division Director, at mmcmahan@manomet.org or tag us on social media!

Backyard BioBlitz

Your yard or local greenspace is teeming with life, from birds to mammals to insects and plants, there could be hundreds—sometimes thousands—of different organisms living in a single acre! All you need to observe and document these living things is a notebook or smartphone and a senses of adventure!

One of the easiest ways to document nature sightings is the app iNaturalist (iNat for short). You may need an adult’s help in setting up an iNaturalist account. Using the iNat app or website, you can list observations of all kinds just by uploading a photo—iNat’s identification software and volunteer identification experts will take care of the rest! Like eBird, iNat has thousands of users—including some specialists who are extra knowledgeable in certain areas—submitting their nature observations every day all over the world. Experts can offer suggestions for what you saw based on the pictures you upload, so you don’t need to be a pro to participate. Head to iNaturalist.org to learn more and start documenting what lives in your area now!

Test Your Counting Skills

The return of spring means that river herring (a collective term for alewives and blueback herring, two species that live in the ocean but travel upstream each spring to spawn), which range from Florida to Canada, will soon be surging up coastal rivers and streams. It is a natural phenomenon that draws predators, such as osprey and bald eagles, fishermen who harvest the fish for bait, and nature lovers enjoying the spectacle of nature’s annual spring renewal. A fun activity for families is to take a field trip to watch the fish migrate upstream. The run generally lasts a few weeks; the start of the run depends on warming ocean waters but generally occurs in regions between March (southern New England) and as late as June (eastern Maine).

Volunteers in many communities help out by counting river herring as they pass upstream. You can practice your counting skills by finding a place along a stream where the fish must pass through a narrow opening as they work their way upstream. Use a timer and see how many fish you can count in one minute. Repeat a few times and compare your findings, keeping in mind that sometimes the fish move upstream in pulses. If your counts are similar you are probably getting an accurate reading; if not, try again.

You can also count river herring from the comfort of your home! The National Marine Fisheries Service and the Town of Plymouth have teamed up to post short videos of migrating herring at  https://www.plymouthriverherring.org/.  These videos are from an underwater monitoring camera installed in Town Brook, where several dams have been removed to allow river herring to migrate upstream. Allow you have to do is watch a video and record the number of fish you see. It’s pretty addictive – you’ll end up watching many! And The website tracks the number of fish counted and estimates of the size of the run. This is a fun and easy activity for all ages – and generates real data that will be used to track restoration of these important fish!

River herring is a collective term for alewives and blueback herring, two species that live in the ocean but travel upstream each spring to spawn.  Alewives and blueback herring are lumped together because they are so similar in appearance that it is difficult to accurately identify them without cutting them open (the lining of the blueback herring’s abdominal cavity is black, the alewife’s, pale.