Syzygy

At some point every summer, there is a "lowest tide".  Low tides (and high tides) aren't created equal; some are lower than others.  This occurs when the earth, moon, and sun are all in alignment -- in syzygy.  Ain't that a grand word?  Three y's, no need for ordinary vowels, rhymes with "misery".  I encourage it's use at your next dinner party.

Every month, there are particularly low tides during new and full moons (spring tides).  And sometimes, these spring tides are really, really low (due to all the astronomical stuff going on around us -- how close our neighbors are; where the planets are, etc).

This week we had a particularly low tide, and at Kent Island that means an expedition to the intertidal.  You never know what you're going to find out there, and that's part of the fun -- it's like an Easter egg hunt -- one that's a bit cold and slimy.  But we all bundled right up and got out there, thankful for good weather on this special day.

First we had to hike down to the south end of the island, wading through the tall grass.  That pole is a sensor that picks up signals from tagged herring gulls.

Headed past the driftwood down to the rocks! 

Our first find -- hermit crabs!

And gigantic Littorina snails -- we have the biggest periwinkles anywhere!

Claire seems unimpressed by this urchin.  But who can resist it?

I'm a huge fan of kelp holdfasts.

And sponges!  This species turns green due to a symbiotic algae living in it.

A giant waved whelk.  Predatory bad ass.

Snail fish.  A favorite!

Aho!  What's this?  The first baby lobster we've found.  You know it's a low tide to find these guys.

Scale worm.  These bioluminesce when preyed on.

Two seastars -- an Asterias and a brittle star -- probably Ophiopholis aculeata.

Lots of Cancer crabs down low.

We took turns flipping over cobbles and catching rock gunnels.

Like this one!

Who knew there could be a waterfall in the ocean?

Interested in tidepools?  Check out these guides:  How to tidepool and Where to tidepool in Maine.

So you don't think it's all smurfs and raisins

Yeah, I have a great job.

But sometimes, you gotta admit sitting warm and cozy in an office might be preferable.  Especially at the tail end of a nor'easter, with gusty winds, cool temperatures, drizzle, and gloomy skies.  On a day when the tide is particularly low, so collecting for class specimens is on the agenda.

Nothing to do but put on the foul weather gear, grab a bucket, and stop whining!

It wasn't all that bad in all these layers.  There's no bad weather, just bad clothes.

I walked along the shore from Dick's Lobster to Potts Point.

Talk about grey . . .

. . . but beautiful.

No one hides from me!  I see you.

Ha!  A tiny little dogwhelk.  There were tons of them, probably freshly hatched.

Now that's some beautiful seaweed.

And the sun tried it's hardest to cooperate!

Stalking Snails with Sarah

Sarah and her snails.

There's nothing better than getting paid to be at the coast.  Last week Sarah Kingston's Marine Molecular Ecology class asked for an assist in finding two types of intertidal snails -- Littorina obtusata (the smooth periwinkle), and Littorina saxatilis (the rough periwinkle).  So off to Giant Steps I went with them, back in my boots.

Intertidal snails clockwise from top left:  Littorina littorea, Nucella lapillus, Littorina obtusata, Littorina saxatilis.  Common names, respectively:  common periwinkle, dogwhelk, smooth periwinkle, rough perwinkle.

There are actually three Littorine species in Maine's rocky intertidal -- the third one being Littorina littorea, the common periwinkle.  Luckily, they have different habitats and morphologies, so telling them apart is relatively easy.

Littorina littorea is ubiquitous in the rocky intertidal, and is found from the Fucus zone down to the bottom of the intertidal zone, including in tidepools.  The common periwinkle is an invasive species that is thought to have arrived on the ballast stones of European trading vessels early in the colonial period.  These ravenous grazers feed on seaweeds, and probably have a huge effect on the rocky intertidal zone.  Interestingly, they have clear preferences for certain seaweeds, so they have changed the species composition of the habitat quite a bit.  You can identify these by their size -- they become large, perhaps an inch across, although they start as small snails so you can be confused if not careful.  The spire of their shell is pointy, and do not exhibit clear sutures between the "layers" of this whirled part of the shell.

Littorina saxatilis (the rough perwinkle) is probably my favorite intertidal snail.  It can be the hardest to find, since it is very small, and is found high above the intertidal, in the splash zone.  These are only common where there are crashing waves -- so exposed headlands are a common place to find them.  These little guys can go many days without being wet, and have almost lung-like organs.  They feed on the black Calothrix (the slick blue-green algae you can find at the top of the intertidal zone).

Hundreds of rough periwinkles hiding in a crack at Pemaquid Point.

"Halos" of Calothrix algae around the cracks where rough perwinkles hide.  They come out of the cracks when it's wet and cool to feed, then return to the cracks when it's dry and hot (to get some relief from the heat).

Littorina obtusata (the smooth periwinkle) is the jewel of the intertidal.  Relying exclusively on knotted wrack (Ascophyllum nodosum) for habitat and food, this snail  mimics the colors of this beautiful algae -- yellow, orange, green, brown, and even red.  They can be tough to find because they are so well camouflaged.

Typical habitat of the smooth periwinkle.

Our mission was to find about 40 individuals of both rough and smooth periwinkles, so Sarah's class can study their genetics.  The first place we looked was in the knotted wrack, and it wasn't long before the first "I found one!" was heard.  Once people got the search image in their heads, we found our quota pretty quickly.  Then it was on to the exposed rocks at the southern end of Giant Steps (where we were very careful).  We had a great look around, then got to work looking in the crevices at the top of the intertidal zone.  Thousands of tiny rough periwinkles were hiding there, so we quickly hauled in our snails.  Not a bad way to spend a Friday afternoon, and I didn't even have to go to the probability lecture that the students sat through after our intertidal adventure!

Found one!

Maybe I got a bit distracted by the anemones in the tidepools at Giant Steps . . . .

A box full of snails.

Aha!  They thought they could hide from me.  No way.

These are dogwhelks -- predatory snails also found in the intertidal zone.  They're eating these barnacles.

Hunting for rough periwinkles.

Checking out our haul.

A photo for Facebook?

Tidepool Explorations: Where To

Maine offers hundreds of terrific spots to get your feet wet and explore tidepools.  Here, in no particular order, are some of my favorites: 

Giant Steps, Harpswell

Giant Steps is one of my very favorite places to explore the intertidal ecosystem.  Looking out over the surf crashing on the ledges and islands of eastern Casco Bay, the site has it all -- a lovely walkway along the cliff, the spectacular "Giant Steps" themselves (a geologic wonder), and wave protected as well as wave exposed sites.  The wave protected site is particularly useful if you're working with students or children, and has some truly spectacular tidepools to explore at low tide.  The wave-exposed parts of Giant Steps should only be explored using great caution, on a very calm day.  These are excellent sites to observe intertidal zonation, however, which can be seen from the Giant Steps themselves. 

The one drawback to Giant Steps is the parking situation (you will notice a theme running through this post).  There is very limited parking, located at the tiny church on Washington Road (and none on Sunday mornings).  Visit in the off-season, or early in the morning or late evening.  Alternatively, park at Mackerel Cove and walk up to Giant Steps (~3/4 mile).  Do not attempt to park on the street.

BEST PLACE TO EAT AFTER EXPLORING:  Morse's Cribstone Grill, after a stop at Mackerel Cove for a photo shoot.  Make sure you check out the Cribstone Bridge too!

Park here -- at the church.

A very low tidepool.

What a spectacular ecosystem!

These are the Giant Steps.  Too bad I'm a not able to capture them with my inferior photographic skills.

The Steps, with distinct zonation below.

A little friend to find.

Potts Point, Harpswell

There's just so much to love about Potts Point.  At high tide, Potts Point is merely an island rising a few feet above the surface of Casco Bay.  At low tide, it offers tidepools, protected sand beaches, pocket marshes, wildflowers galore, and spectacular views of boats making their way through the cut between Merriconeag Sound and Potts Harbor.  One very interesting feature of this site is a shallow pool just to the east of the island with a very dense substrate, which is home to clams that can't burrow very deep.  You can easily observe their siphons, but you can't dig them out -- that's how hard the substrate is.  (I believe it's compacted detritus from an old salt marsh.  Very interesting.)  This is an outstanding place to explore with children, with minimal wave action but lots to see.

One of the charms of Potts Point is the walk from the parking area (near Dick's Crab and Lobster Company) to the preserve.  You'll pass traditional summer cottages, owned by generations of the same family.  In summer, kids will be racing around on land and sea, and "rusticators" will be enjoying their summer homes.  Again, there is limited parking.

BEST PLACE TO EAT AFTER EXPLORING:  I'm an absolute sucker for Dolphin Marina.  This family-run operation offers the best fish chowder in the state (aided by the huge blueberry muffin that comes with every serving). 

What a spot!  Wow.

An unusual chance to see clam siphons.

Sunset, anyone?

Amazing pocket marshes!

There are lots, and lots, of dog whelks.

Wow.

Ocean Point, Boothbay

Last year, my students and I were doing some research at Ocean Point, when a woman from Germany started to chat with me.  She was on a month's holiday, and she'd been all over Maine, but she said after all that exploration, she wished she'd just stayed here the entire time.  I know exactly what she means.  This is a great place to walk along the shore, bring a lawn chair and sit for an afternoon, or enjoy the views of Monhegan and the other surrounding islands.  There is a public walk, maintained by the Ocean Point Association, and plentiful parking (miracle!).  This is another great spot to compare wave-protected sites to wave-exposed sites.  (In fact, that's exactly what my students do there every fall.)  At very low tide, there are some spectacular tidepools, full of seastars and crabs.  Use caution, of course, but enjoy the crashing surf on this peninsula. 

BEST PLACE TO EAT AFTER EXPLORING:  This is a tough one, as I've never eaten when visiting.  Any suggestions?

Ocean Point is an old summer colony.  The one percent "rusticate" here.

From the parking lot, walk to the east of the little cove.  Look for this sign.

Look at the distinct zonation apparent here.

A low tidepool.

Pemaquid Point, Pemaquid

This is one of the most spectacular, most photographed sites in the state.  The granite outcrops descending from the lighthouse are worthy of the cover of National Geographic.  But the tidepools are also a world-class resource.  Here you'll find tons of Littorina saxatilis, which thrive in the huge splash zone; tidepools full of pink coralline algae; and a variety of sea creatures.  In summer, there is a fee to park, but the lighthouse and museum are open, making it worth the price.  Bring a picnic and it'll be a fun-filled day.  This is a site where you should use extreme caution, as surf can be huge and impacts dangerous on this exposed peninsula.  If there are waves, come back another day.

BEST PLACE TO EAT AFTER EXPLORING:  Well, how could I resist the King Eider?  Their lentil burger is out of this world.

No wonder it's on our state quarter.

Barnacles and mussels dominate this pool.

Again, lots of zonation.  See the wide band of barnacles?

Rachel Carson Preserve, Edgecomb

Sometimes, there are heroes amongst us.  Rachel Carson was one of the great environmental heroes of the twentieth century, and like so many of us, she was inspired by Maine's spectacular coast.  Carson spent many a summer in nearby Boothbay Harbor, inspired by Maine's fog, waves, and sea creatures.  Her three books, Under the Sea Wind, The Sea Around Us, and The Edge of the Sea are classics, and well worth a visit to your local library for a check out.  The Rachel Carson Salt Pond Preserve, perched on the edge of Muscongus Bay, is the site where the great naturalist gathered material for the Edge of the Sea, and is today preserved in perpetuity by the Nature Conservancy of Maine (which, by the way, Carson helped found in the 1950's). 

The small tidepool at this site, merely a quarter acre, is the perfect place to introduce children to the wonders of the ocean.  At low tide, this is a site with virtually no waves, so is particularly safe.

BEST PLACE TO EAT AFTER EXPLORING:  If you've never explored New Harbor, just down the road, then a stop at Shaw's is a great idea.  New Harbor is working waterfront at its best, and lunch on the deck at Shaw's gives you a front row seat as lobstermen offload their day's catch. 

Park here.

The protected tide pool.

Schoodic Peninsula, Winter Harbor

Here's a little secret:  Acadia National Park is more than just Mt Desert Island.  So if you want to escape the crowds that flock to the island every summer, head on over to Winter Harbor, just east of Acadia.  There you'll find the Schoodic Peninsula -- still a part of the park, but much quieter.  From here you'll get a spectacular view of Mt Desert's summits across Frenchman Bay, and you can checkout some truly amazing tidepooling.  Three sites are worth a stop.  First, stop at West Pond, which is relatively protected from waves.  Here, you'll be able to find tons of crabs, seastars, urchins, and anything else your heart desires.  Schoodic Point is a spectacular stop -- but can be very dangerous.  As the National Park Service brochure tells us:  "The ocean views are spectacular, but the footing is dangerous -- people have died here.  Wet rocks are slippery, and waves can sweep you into the sea."  Let me reiterate:  PEOPLE HAVE DIED HERE.  So, don't be dumb.  Don't get too close to the edge and don't get near the shore if there are waves.  I don't want to read about you getting the next Darwin Award, got it?  A final stop for tidepooling is at Blueberry Hill.  Here, focus on the shallow sandy pool just west of the parking lot -- where you'll find sand dollars if you're lucky.  

At ALL these sites, watch the waves, and pay attention to the tides.  Go when the tide is going out, and skip the tidepools if the sea is angry.  Seriously.

A great place to find . . .

seaastars!

By the Blueberry Hill parking lot, you can find these guys in the big sandy pool.  Do NOT collect them, they are alive!