High tide marsh life

If you live anywhere near the coast you may have noticed that this most recent full moon has yielded some very high tides.  In fact, Morrissey Boulevard, where UMass Boston is located on the Boston harbor, had signs warning that the roads were likely going to flood on the over night high tide.  Although I was simply excited to see general tidal information being displayed to the public, I realized this is the perfect opportunity to talk about what happens in a salt marsh when the tide comes up.

Salt marshes, like most coastal ecosystems, undergo a big change once or twice a day when the tide goes in and out.  In a matter of hours they go from a mainly terrestrial habitat where a marsh ecologist can walk around in, providing they have Muck boots, to a completely subtidal, underwater ecosystem.

When high tide hits the marsh, a whole world of marine animals- from fish and shrimp to crabs and birds, come into the marsh creeks to take advantage of the rich resources that aren’t available before the water grants them access.

Figuring out what happens during high tide is often difficult.  Some researchers use nets to catch everything that comes into the marsh at a high tide.  Others use “single line sampling” which is what marine biologists call going fishing.  Recently in a number of different ecosystems, researchers have been using underwater photography or videos to see what we normally can not!

So- what happens in the marsh when all of that water comes in?  We put out some GoPros at the edge of the creek as the tide was coming in and this is what we saw:

 

In the video you can see at least 3 different fish species, as well as a crab and a lot of grass shrimp.  These critters feed mainly on the algae and detritus that is on the surface of the marsh mud.  Every time that the tide comes in, a new batch of algae is deposited onto the mud, providing an all you can eat buffet!

 

 

South shore marsh with a 10.5 foot tide coming in

South shore marsh with a 10.5 foot tide coming in

 

 

 

Marsh Vacuum? Marsh Vacuum

An enormous component of what creatures live in the salt marsh are tiny insects and speedy spiders.  Because of this, we have developed a highly technical method of catching things like mites, spiders, flies, grasshoppers, amphipods, or beetles– a giant marsh vacuum!

The Marsh Suction Sampler is simply a Stihl leaf blower with a vacuum attachment placed on the air intake valve. The end of this attachment, made from a flower pot, is lined with fabric (muslin cloth or tulle work the best) to collect all the animals that are sucked up.  Once the whole plot is sampled, we take the cloth off and place it into a Ziplock.  Then we take the sample back to the lab and, under a microscope, count and identify all of the bugs that we sucked up.

Below are a couple of pictures from that first sample.  We found high total abundances and a great diversity of bug-types including ferocious but minuscule spider predators, scavenging beetles, excited crickets, biting gnats, spastic flies, and (my personal favorite) the beautiful red velvet mite

 

 

 

 

Suction sample from Squantum marsh

Suction sample from Squantum marsh

A second sample of the insect community of Squantum Marsh

A second sample of the insect community of Squantum Marsh

 

Welcome to Marsh Life!

Hello and welcome to MarshLife.org! If you live near the marsh, like the marsh, want to know more about the marsh, or have ever seen a marsh, then you have come to the right place.

Here at Marsh Life, we are a group of marine biologists who are trying to figure out what makes the marsh tick, what the marsh does for us, and what we can do for the marsh.

This blog will tell stories about the creatures that live in the marsh (like crabs and snails), visit the marsh every day (like fish or shrimp), or just stop by every once in a while for a quick meal (like osprey or egrets).

Along the way we will reveal some of the most innovative and creative techniques to sample marsh life (such as The Marsh Bug Vacuum). We’ll visit some of the most famous marshes in the world (like Cape Cod and Nantucket), and some of the people studying them (scientists & managers, get ready for some Google Hangouts!). Last, we’ll share our insights and those of others as to how marshes are changing and what we can do to help them.

So sit back, and get ready to enjoy our tales of marsh life.