Summer's over

September has begun! Where did the summer go? I was on the beach this morning watching a large flock of sandpipers feeding at the tideline. There must have been perhaps 200 birds there. Not sure what species, but I think at least Piping Plovers. Seeing those birds feeding like crazy in preparation for their migration to South America really made it obvious - summer is over now.

This morning I kind of overslept and missed the low tide. I had come down to collect some Porphra - which is a very thin papery type seaweed like Sea Lettuce. This type of seaweed seems to have several forms - maybe subspecies. Some grows at the mid-tide line and is attached to small rocks in a sandy/ gravelly area. Another type is found only in areas of high current, this one is much darker and tougher and is towards the low tidal part of the beach. I did have to wade out to collect a few samples for a customer - so I considered myself lucky that didn't miss the 'boat' altogether. Had hoped to pick a few kelp plants as well but as you know you have to be at the low tide to find any of those.....

A few days ago the remnants of a hurricane driven storm came through our county with lots of rain and wind. When I reached the beach this morning it was not surprising to see a large beach-side windrow of 'storm-cast' rockweed stretching along the cobbly shore. It was a mixture of Fucus or bladder wrack and another type, Ascophyllum or Knotted Wrack. It was interesting to dissect out the windrow a bit and see just how Mother Nature had delivered this resource to its beachside location as well as what was found living inside. Initially I suspected that the winds must have torn the plants from their holdfasts (structure that attaches them to the rocks) but no - it was quite different.

What seems to have happened is that the storm's power actually loosened up the small stones upon which fairly large clumps of rockweed were attached. Rockweed is a name we use for a group of brown seaweed species found in the intertidal in great abundance. These stones of orange and grapefruit size are often buried in the beach substrate and provide a good solid place of attachment for rockweed plants. Once the wind and the waves hit them it is apparent that their foothold on the beach gave way and they became mobile. Because of the floats on the rockweed, that is their air bladders, provided enough floatation for the rocks to then be carried up the beach and into the tangle of other 'storm-cast' seaweed at the high tide line. See my UTube video about this seaweed and what happened to it in this storm. Besides rockweed there were bits of Spartina grass, little beach fleas, and other organisms found inside.

Have to share this picture of some sea cucumbers we had here at Gulf of Maine this summer. What a fantastic pile of sea pickles. I just dove my arms into the mass to see what they would feel like..... it was creepy. Sea cucumbers do respond much to touch other than to purse up their tentacles and wait for danger to go away. These guys came from a fisherman in Milbridge, Maine. Ug!

Wow - pouring rain here in Maine today!  Nice to be inside, but I need to go dig some sandworms - guess I will be getting wet.  Haven't blogged in a long time - had a 2 week trip to Peru compliments of my son winning a National Geographic Kids contest.  What a trip it was!  15 kids from across the nation were chosen based on their essays and a photo they submitted.  Dewey took his of some Brachiopod fossils in the shale on the beach in front of our house.  They look like the picture below.   We can talk more about these sometime. The kids and I, cousins, friends, etc. love finding fossils on the beaches in our area.  A neighbor just gave Dewey a fossilized coral they found locally.  We are still waiting to learn where they found those!

I wanted to share my collecting notes from yesterday when I was finding Dwarf Britttlestars, genus Axiognathus,  in a local tidepool.  It took me years of chancing upon these little Echinoderms before I realized that they were not just small Daisy Brittlestars, genus Ophiopholus but a new species to me.  I needed to find a few dozen of these critters for a Gulf of Maine, Inc. customer and with my experience I knew right where to find them.  

The key habitat for Dwarf Brittlestars seems to be in shell mounds.  We find them hidden among cast blue mussel shells.  They are a bit hard to spot at first, and they are not kidding when they call them "BRITTLE" stars.  Not only are they tiny, one has to handle them with kid gloves so to say.  The best way to pick them up it to not directly pick them up.  We scrape them onto shell pieces so that when they end up in our buckets, they go substrate and all.

So I headed to the tidepool on a sunny morning and managed to hit the tide at just the right time.  Dwarf Brittlestars prefer to be subtidal, but you can find them at the lower end of low tides in your area.  I believe that like any tidal specimen as long as they can stay moist and protected during the drain off of the sea they will survive until the flood tide comes again.

I use my hands like a small dredge in low wet areas to scoop up  handfuls of shells and debris and then I spread this out on a flat surface like a rock or on a ledge.  Then by carefully sifting through each shell I can look for their fuzzy little arms (rays) to tip me off to where they are hiding.  Often you will see only  one ray protruding from the shells, but with experience they become easier to spot.   I am not sure, but I think these guys feed on detritus.  Whenever I get a big order of these for Gulf of Maine, Inc.  I try and find a submerged mound of shells that seems well silted and muddy. The muddier the shell mound the better the habitat.   Once I found a one gallon plastic milk jug that had been sitting on the sea floor for a long time.  When we emptied it of muddy silt, out came a pile of dwarf brittles.  It makes sense that this habitat would work well for them not only for feeding, but for protection.

It did not take me long to get the stars I needed to fill my order and to head off to work.  I saw lots of Silky Sea cucumbers, Limpets, Scuds, Trumpet Worms, and other inverts as I collected but did not need any of those at this time.  Will get those later - it was time to head out.  Lots to do as I have been away from the office for about three weeks and it is time to catch up.  Catch me next time in the tidepools! - TT

Fisherman's bucket

Hermits, hermits, hermits!     Yesterday a local fisherman Mike brought us in a pile of goodies fresh off his sea urchin drag boat.  The weather had finally warmed up and the seas subsided enough for him to go out safely and try and make his living.

Besides the sea stars he brought in, I had asked him to keep an eye out for some hermit crabs and other small invertebrates.  The hermits were HUGE - mostly Flat - Clawed variety, but there were some Hairy Hermits as well.  Some of them were a bit stressed due to the anoxic conditions in the small pail and they had exited their shells. This was a bit concering, at first - I wondered how they would do outside their shells.  I placed them into my tank 'naked' for the evening and when I returned in the morning, they had all found suitable shells to move back into... 'shall I slip into something a bit more comfortable...?'.  To my surprise, many of the hermits were egg laden (gravid, berried?).  You wouldn't be able to see this unless they had come out of their shells.  The eggs look just like a lobsters egg mass.  The color was very black and the eggs a bit smaller though.

Hermit crabs are one of the easier marine inverts to take care of  in a tank.  I feed mine bits of clam or  squid when I have it.  They will all gather round a lump of feed like cows at a trough, snipping and tearing bits to feed into their mouths.  It is pretty neat to watch.  As for the  shell species that were represented - there were all the major mollusc snails we have here in Cobscook Bay.   Wave Whelk shells, Moon Snail shells, Stimpon's Colus shells, and Dogwinkle shells.  The Moon Snail shells are the most impressive.  Since these snails get very large, the Hermits that inhabit them are big too.  

As for other species that came up in the fisherman's trawl, we found tunicates, other crabs and worms.  There were several Toad Crabs - Hyas genus.  The largest of these was about 8" across.  The Sea Squirts in the pail were Sea Grapes  (Molgula), Sea Vase - Ciona, Sea Potatoes - (Boltenia), and Sea Peaches (Halocynthia).  All of these was cemented to other tunicates in clusters or they attach to mussels,, rocks, and other debris.   Final inspection of the pails contents revealed some fan worms, finger sponge, scaleworms and some tiny isopods - benthic creatures that had come up in the holdfasts of the tunicates and sponge.  I dumped the remainder in our tanks.  Hopefully they will adapt to the smaller quarters and find there niche - it's a crab eat , worm eat, snail eat world in there! - TTim

Sea stars - aka Starfish

Starfish or sea stars are probably the most celebrated of  all tidepool life.  It does not matter what shore, dock, rocky ledge or beach you find yourself upon, you can usually find sea stars.  They are easy to find, easy to keep and no matter how many you find you always have to pick up another to give it a good close look.  They are fascinating!

The Northern Sea Star is the name of our most common star here in Maine.  They come in all sizes and colors.  A good challenge for classes at the beach is to see who can find the smallest star of all.  It is surprising - once you look in the right places very small stars can be found.  The smallest ones we have located are usually in the pouches of another species - the brood star. This particular species actually spawns and 'broods' its young.  There are usually dozens clasped in this oral area beneath the star.  When found it appears they are feeding, but rather they are just protecting their young.  They could be mistaken for a food source or part of its stomach, but if you you closely enough you will see little orange stars clustered within.  Now those are really small stars.  Small 1/2" to 1'4" stars can be found under rocks, in crevices, or attached to the holdfasts of seaweeds.  Another nice thing about small stars is that they can be dried out for classroom use without any chemicals or stinky smell and they keep well for years.

I am not sure what causes the Northern Sea stars to vary so much in color, but I have an idea that it may depend on their diets.  We have colors like tan, brown, red, pink, purple, and orange.  The largest ones are often a purplish color with orange highlights.  In the early summer the stars fatten up - their gonads (sex organs) ripen and they are ready to spawn.  It is at this time that my kids and I have great fun wading at low tide to find these beautiful pinkish-purplish monster stars.  The largest one we have found here in Cobscook Bay was 28" from tip to tip.  

Once you find a good place for stars you can always count on returning to find them again and again.  Stars love structures such as pilings, rocky ledges, overhanging crags, docks, and cobbly sea bottoms.  Besides grouping up for spawning purposes in early summer the best place to find them is on good feeding grounds.  For sea stars this means a place with lots of blue mussels or perhaps oyster beds.  Once you find a mussel bed you can find stars actively feeding.  The way to see if they are feeding is to look for stars that look all 'balled-up'.  The center of the star will be very visible but some of the arms will not.  They will be folded around the prey, tube feet in action doing their best to open the shell of the hapless bivalve.  If you pick the star up and flip it over you will often see the large watery stomach structure hanging out all over the place.  As the water drips from the animal and it's prey the stomach will often be drawn back into the cavity from which it was extended.  It is great fun to see.  Students will find some in various stages of feeding.  Many times the star has already finished it's mollusc milkshake and only the empty shells remain between its arms.   Burp!

If you look closely at a live sea star it is easy to quickly find the points of interest.  Starfish have the radial symmetry plan with their 5 arms stretching outwards.  Tucked in at the base two arms is a tan or orange madreporite or sieve plate.  It looks a bit like an eye without pupil in it.  This is how water enters the star's  hydraulic system.  It helps her/him pump up tube feet so that it can move.  Another feature to observe is the very spiny hard skin that stars have.  It is like a very rough sandpaper.   If the star is live - lay it on a rock and watch the very slow movements of the animal on this surface.  Stars do not have eyes but rely on touch.  You will see the very tips of the stars arms curve upwards to 'reach' for another rock, or piece of seaweed upon which it could move.  It is feeling its way around to see where it is.  Kind of like a person in their dark bedroom feeling for the light switch.  If you watch stars underwater you will see that at the tip of each arm are 6 - 10 small elongated tube feet that are constantly 'feeling' around for new structures upon which to crawl.   These tube feet are very very thin and hairlike and are like a snail's or lobsters antenna.

Flip the star over to see the grooves in the bottom of each arm.  Deep inside the groove are hundreds of larger tube feet that are used to move.  The tip of each has a bit of a suction cup - these all work together to give the star traction on the seafloor moving it along.  Each side of the groove have little spines that actually move - these are called - you guessed it "movable spines".  They are finer in size than the immovable spines that cover the topside of the animal.

 At the very center of the animal is the mouth or oral cavity.  When feeding, the stomach will protrude and/or  retract through this hole.  If observant it is sometimes possible to look closely at the mouth and see a bit of the stomach up inside the hole - especially if the animal has been feeding recently.  Like any coldwater invertebrates - sea stars do not have to feed very frequently and probably do not do much feeding in the winter when temperatures are low.  Once spring comes they must gorge themselves to provide nourishment for their reproductive organs.  Upon dissecting an large sea star in May or June - you will find a HUGE digestive gland and BULGING gonads that are ripe with sperm and eggs.  When the temperature is right males and females release their sex cells into the water simultaneously and larval stars are born!  Voila - the miracle of life.  I have witnessed this only a couple of times in tidepools  in the summer.  It looks like tiny confetti or milk oozing from the topside of the animal.  Seems to come right out through their skin.  

Sea stars are a lot of fun!  Kids love them and I guess I am just a kid.  I have found and held literally thousands of different stars over the years.  Each one is worth looking at and they all seem to be unique in some ways.  Occasionally we will find a star with 6 or 7 arms.  I have seen arms that split half way down resulting in a y shape or what appears to be a side growth arm - a mutation of sorts.  Thats all now for Northern Sea stars.  Another time we can talk or highlight the other 7 species of stars that are found in the cold Atlantic waters.   - Tidepool Tim   

 

Blog birth - Tidepool Tim - Winter clamming

Hello there -

This is my first attempt at a blog. I've heard about them and read a few to date.  Feels a little weird writing, but for a guy who has kept umpteen journals over the years and written a column for a teeny little paper - I'm sure I will get up to speed fast.

January cold!   Tucker and I headed to Kelly Point yesterday at dusk to see if we could scare up a feed of clams. Temps were in the single digits, but the snow had stopped and we thought that the flats would still be diggable.  Had to snowplow our way down the road as the drifts were massive in some places.  We did manage to blast our way through and right to the high tide mark.   The flats were white with snow towards the upper intertidal but we could see that further down the mud still held the oceans relative warmth and that the snow had been melting there - a good sign!

We raced down the embankment with diggers and hod in hand.  We were in the lee of the wind and felt like we would have enough light before dusk to perhaps get 1/2 peck or so for the family feed.   The mud felt ' cake-like' to our rubber boots  it is a weird sensation to walk on this stuff.  The mud is frozen on the top and goopy underneath.  So long as you keep moving you won't break through. Farther down we hit sandy beach that was frozen solid - it doesn't hold the water and the warmth as well....  

We took note of the many small mounds or  'volcanoes' as we call them.  These are from the castings of the lugworms who are huddled below the cold in their u-shaped burrows.  In the spring there will be some digging there to do.    Some Black ducks exploded from the water near the ledges at low water - there were several groups all taking flight out and over the river bay.  They usually kept to more open water area but must have been hiding from the wind as we were.   We scurried along towards low water until we started to see the clam holes in the mud marking the siphons.   There were lots of tiny holes and very few large ones but we picked our spots and went to work.

"Got a nice one" and "aw nuts - broke him" were all I heard from Tuck as I managed to pull 4 small clams from the sand.  I crushed the largest one with my digger.  By that time my rubber gloved hands were already aching from the cold.  The wind had picked up as we had moved far out on the point and well beyond the shelter of the land and trees.  

"How you doing?" I asked. "Just two small ones so far" he replied.   "I'm cold"!   We stumbled around for a few more minutes enough to notice how fast the liquid mud was freezing to our boots.  Enough said - we bolted up the beach back to the truck.

So much for our January tidewalk.  We had hoped to go looking for scaleworms after clamming but that obviously was not going to happen today. The full moon had offered us huge tides, but it was just too cold to be out on the beach.  We chugged home and dropped the plow in the drive on the way back in.  No clams for dinner this time - but it was neat to be out for a try!