Last week on a transect survey at Lovell’s Island we found a shrimp in a tide pool. We took photos in the field and released the unknown, egg bearing shrimp.  Upon returning to the lab we tried to identify it from the photos, and we found it almost immediately: the European rock shrimp, Palaemon elegans.  It was a perfect match; the translucent body, the dark striping and the tell-tale orange and neon blue claws were all present.  Unfortunately, the European rock shrimp belongs in Europe.  It was an alien invasive.

Sure wish we hadn’t released it now… it was full of eggs.

The European rock shrimp is a fairly recent invasive,  first sighted on the East Coast in 2010  in Salem and Gloucester, MA.  However, this is the first time it has been sighted in the Boston Harbor.  To make sure  that it really was a European rock shrimp, we went back to Lovell’s Island to collect samples.

We didn’t think we would be successful: we had found one shrimp, in one tide pool, on one day. We were wrong.  We weren’t even finished unpacking our gear when Chris McIntyre, our resident shrimp expert, found one adult shrimp. And then another. Within a couple minutes we had several whirl bags and a Tupperware container full of twitching, wriggly, egg bearing shrimp that all looked exactly like the European rock shrimp.

Net full of babies

Rock Shrimp in a whirl bag

Wriggly tupperware

Since there was such an abundance of adults and babies (one sweep of a tide pool with a net caught over 20  baby shrimp) Chris decided to take the shrimp to U. Mass, to see which native fish would eat them. We brought a few back to the lab, preserved them in ethanol, and they promptly turned bright red.

Hopefully this discovery will help in the mitigation of the European rock shrimp, and stop it before it takes hold of the Boston Harbor Islands.

After waking up bright and early (a little bit too early for coherent thought if you ask me) we caught the T and headed to Boston Harbor. Its a bit of a walk to the ferry, especially carrying giant, cumbersome, green buckets full of equipment.  But, thanks to the continued time-management skills of Kate Longley, we made it in plenty of time and got on the ferry without incident.

Unfortunately in order to get to Lovells Island we first had to make a layover at Georges Island. It was a forty minute wait, but the island had l-o-v-e-l-y wooden chairs overlooking the beach. Very relaxing. We read, we slept, we watched geese and then we missed out ferry. Apparently it had arrived five minutes early and left  unannounced. Luckily we got a ride from a wonderful two-man water taxi, who changed their route for our sake.

One disappointingly short ride later, we arrived on Lovells island. It was quite a bit of a hike to get to the field site, not helped by the sand, the gravel or the occasional large cobble  stone that would sneak into our shoes.

The field site itself was wonderful. A relatively flat area that stretched further out into the ocean than the rest of the beach. We arrived there shortly before low tide so we were surprised at just how wet everything was. Across the site was a series of warm, interconnected tide pools full of large rocks. As awesome as this was for research, they made for slippery going and we had a couple of close calls.

View of the sie, and Isabelle and Pavlina setting up our transect lint

The research was excellent as well. Unlike our visit to Spectacle Island there were no “empty” quadrats. The tide pools were excellent for algae (specifically Chondrus crispus and Fucus) as well as periwinkles (at one spot we found over a hundred). We even found some tunicates!  Like Spectacle however, there was an over abundance of crabs. Introduced asian shore crabs, to be exact.  They were everywhere and it was always a scramble to grab them before they hid under new rocks.  Isabelle and Jeffery overturned one rock that had over twenty crabs underneath!

Scrambling for crabs

Bucket of over twenty crabs!

This particular crab was trying to steal Isabelle’s ruler.

Monster crab – the largest Asian shore crab we’ve found so far!

And afterwards we were treated to ice cream by Kate! I suppose one way to describe the day would be “crab-tackular” (please pardon the pun, I promise I won’t do it again).

~Carolann