November 12, 2018

Seaweeds, Marine macroalgae of NYC

I recently got curious as to which species of marine macroalgae I had observed so far in NYC. Here is an attempt at a list. Nearly everything is from Randall's Island; others have their localities mentioned:

Sea Lettuce -- Ulva latuca
Gut Weed -- Ulva intestinalis
Ulva spp
Bryopsis sp.

Rock Weed -- Fucus distichus
Bladder Wrack -- Fucus vesiculosus
Ribbon Weed -- Punctaria plantaginea [Soundview Park]
?Ectocarpus siliculosus? or something similar-looking which grows attached to hard substrate.

Grinnell's Pink Leaf -- Grinnellia americana
Agard's Red Weed -- Agardiella subulata
Irish moss -- Chondrus crispus
False Irish Moss aka Turkish Washcloth -- Mastocarpus stellatus
Red Puff Balls -- Spermothamnion repens
Rusty Rock -- Hildenbrandia rubrum
Gracilaria ?vermiculata [Fort Tilden]

I hope to add to this list and/or refine it as I go along. Maybe I can add some nicer images too.

Posted on November 12, 2018 01:09 AM by susanhewitt susanhewitt | 6 observations | 2 comments | Leave a comment

September 10, 2018

Weed Whacked in NYC -- where did my garden go?

This morning I took Daniel Atha of the New York Botanical Garden to 87th Street to show him two really good local plant finds, so that he could take samples to press for the NYBG Herbarium.

The two plants were the Scarlet Creeper:

And the White Morning Glory:

Both species have only ever been recorded once before in NYC. The new occurrences I found meant that these two species are probably now established in NYC, whereas the first occurrences could have been just "waifs", of no lasting significance.

Alas... when we arrived there, I was astonished to discover that the entire very long raised bed had been weed-whacked right down to the ground. It had been just fine on Friday morning and now early on Monday morning -- nothing left standing. This raised bed had over 65 plant species growing in it, all spontaneous -- an amazing diversity. A large proportion of the plants were native species, i.e. what I would consider to be wildflowers. There were no garden plants in this raised bed at all -- it seems that nothing had ever been deliberately planted here, or if so, it had all died out long ago.

Fortunately the person who weed-whacked the bed had not dug up the soil. I hope they have no intention of planting garden plants in there. Perhaps the weed-whacking was just a "fall clean-up" by some garden company that has a contract with the building?

If they now leave it alone, probably most of the plants will stage a come-back, either this year during the remaining warm fall weather, or failing that, the plants will hopefully come back again next year. I am sure that most of the plants had dropped seeds into the soil.

I do have iNat observations/photos of all the plant species I saw here, but the Herbarium material would have been a permanent formal museum record.

Ah well, such is life! We need to educate people that biodiversity is GOOD. Do not shun a fine diversity of spontaneous plants.

Posted on September 10, 2018 12:16 PM by susanhewitt susanhewitt | 3 observations | 17 comments | Leave a comment

May 07, 2018

I grieve for the overly widespread use of the Weed Whacker!

I am currently on the small island of Nevis, St. Kitts and Nevis, Leeward Islands, West Indies. My husband and I have been coming here on annual visits for 21 years, this time for four weeks.

The island used to have a severe litter problem along the main road, but, over the years that has been almost entirely eliminated, which is really great. However, this year the verges of the main island road (and some other pieces of public land) look almost uncannily neat and tidy, and that is in large part due to deployment of numerous Weed Whackers, which is more or less a new technique here.

I suppose I should be celebrating this neatness, but I love weeds. I find them very interesting in themselves, not to mention the surprisingly rich range of other wildlife that lives in and among the plants that flourish in open areas which are not completely overgrown, but are nonetheless somewhat neglected -- benign neglect.

The rental house we are staying in has a yard, quite a small yard, that surrounds the house. I spent the first week or two here photographing every organism I could find in the yard. That was because I was in a medical CAM boot and was not allowed to walk around much. I did surprisingly well, I thought, in terms of what I found. There are very few garden plants in the yard, but the weeds were doing well and many of the smaller weeds were flowering. They supported quite a range of bugs, including at least four species of butterflies.

But then, after those two weeks the gardener came and weed-whacked everything right down to the ground. Where did all the nice bugs go? Goodbye to the several different species of butterflies that used to cruise the yard and settle on some of the Tridax Daisies.

Alas, alack, the weed whackers. Does the trimming have to be so complete and ruthless?

Posted on May 07, 2018 12:45 AM by susanhewitt susanhewitt | 8 comments | Leave a comment

April 18, 2018

Earthquake today!

At 4:26 this afternoon it felt like an explosion had taken place on the island of Nevis, like a dynamite charge had gone off, but no "bang", just the whole island going "WHUMP". Then I could feel rocking, clear waves back and forth, about one every half a second. However that only lasted about 8 or 9 seconds, and then it stopped.

I recognized it as an earthquake, having been through one or two when I lived in California. However this one was lower frequency and higher amplitude waves than the ones I felt there, and therefore more impressive.

So it turned out it was a 4.7 earthquake going off under Antigua and Barbuda, which is only 60 miles east of where I am, on the island of Nevis. This counted as a "light" earthquake, not at all serious. Interesting though, and it sure makes you pay attention. :)

I did not hear any birds or dogs responding with alarm, but maybe they take it all in stride.

Posted on April 18, 2018 12:46 AM by susanhewitt susanhewitt | 4 comments | Leave a comment

April 17, 2018

Forced to concentrate...

I am on the lovely Caribbean island of Nevis for four weeks, but I have my left foot in a stiff and heavy medical CAM boot, and the right foot with a big rubber "even-up" layer strapped onto my sneaker. This is because of severe Achilles tendinitis (correction -- tendinosis) in the left leg, and therefore I am also under doctor's orders to minimize my walking as much as possible.

This has some pluses as well as some minuses. Although I can't walk down to the main road and go to the various beaches every day on foot or on the bus as I usually would, I can nonetheless walk around the small yard of the rental house to some extent, or even go up and down the lane a little bit, as long as I am careful not to do very much.

Because my scope for exploration is severely limited, this is causing me to concentrate my awareness and my searching efforts, in order to find as many different species as possible within this small and somewhat ecologically impoverished area of a few houses and a few vacant lots that are mostly overgrown with invasive species.

I think this is actually good discipline for me as a naturalist! I have to focus really intently and therefore manage to find things that normally I would not notice.

I have included here some of the more picturesque things I have found so far in this small area.

Posted on April 17, 2018 11:49 PM by susanhewitt susanhewitt | 21 observations | 2 comments | Leave a comment

March 05, 2018

Mollusks from Randall's Island, an update


From April 2017 to March 2018. The marine species were (all but one) found by me. Cedric Lee found many of the most interesting terrestrial species, and the Succinea sp. was found by Danny Molinaro, who was then part of the Natural Areas Management team of RIPA.

Note: species in square brackets may or may not actually live in the estuary around the island.



Mytilus edulis, Blue Mussel -- fresh dead
Geukensia demissa, Atlantic Ribbed Mussel -- live
Argopecten irradians, Bay Scallop - few old valves
Crassostrea virginica, Eastern Oyster -- live
[Astarte castanea, Smooth Astarte -- one old dead valve]
Mulinia lateralis, Dwarf Surfclam -- live
[Spisula solidissima, Atlantic Surfclam -- one broken piece]
Ensis directus, Atlantic Jackknife Clam -- live
Macoma balthica, Baltic Macoma -- live
Macoma tenta, Shining Macoma -- one shell, paired valves
Ameritella agilis, Northern Dwarf-tellin -- live
Angulus versicolor, Many-colored Tellin -- one shell, paired valves
Mercenaria mercenaria, Hard Clam -- live
Mya arenaria, Softshell Clam -- live
Rangia cuneata, Atlantic Rangia -- single valves
Cyrtopleura costata, Angelwing -- fragment, juvenile
Teredinidae family, Shipworms -- many
Lyonsia hyalina, Glassy Lyonsia -- a number of paired valves
Total 18


Littorina littorea, Common Periwinkle -- live
Assiminea succinea, Atlantic Assiminea -- live
Crepidula convexa, Convex Slippersnail -- two shells
Crepidula fornicata, Common Slippersnail -- juvenile shell
Crepidula plana, Eastern White Slippersnail -- live
Neverita duplicata, Shark Eye -- several
Urosalpinx cinerea, Atlantic Oyster Drill -- several
[Busycon carica, Knobbed Whelk -- juvenile shells]
Tritia obsoleta, Eastern Mudsnail -- live
Boonea bisuturalis, Two-Groove Odostome -- live (one)
Haminoea solitaria, Solitary Glassy-bubble -- several
Melampus bidentatus, Eastern Melampus -- live
Myosotella myosotis, Mouse-ear Ovatella -- live
Total 12

NOTE: I am not including here all of the exotic species I have found – shells that were presumably brought to the island by humans and then left here for a variety of reasons.



Physa sp., -- Live in freshwater pond
Viviparus georgianus, -- one worn shell on Wards Island beach
Dreissena bugensis, -- one intact fresh-dead shell, Wards Island beach, inside an oyster shell – possibly this species is now invading estuarine waters?
Total 3


Cepaea nemoralis, Grove Snail -- many colonies
Deroceras reticulatum, Milky Slug -- several live
Deroceras sp., -- few
Oxychilus draparnaudi, Draparnaud’s Glass-snail -- live
Vallonia excentrica, Eccentric Grass-snail -- live
Arion intermedius, Hedgehog Slug -- live
Zonitoides nitidus, Shiny Glass-snail -- live
Zonitoides arboreus, Quick Gloss Snail -- dead
Cochlicopa lubrica, Slippery Moss Snail -- live, fairly common
Discus rotundatus, Rounded snail -- common live
Vertigo pygmaea, Common Whorl-snail -- live, one colony
Hawaiia miniscula, Minute Gem -- live, one colony
Paralaoma servilis, Pinhead Spot Snail -- live, one colony
Succinea sp., Amber snails -- one live
Total 13

Specialized salt marsh species living in the Little Hell Gate Salt Marsh

**Assiminea succinea, Atlantic Assiminea -- many
Melampus bidentatus, Two-toothed Marsh Snail -- many
Myosotella myosotis, Mouse-eared snail -- many
Total 3

**Please note that the Assiminea succinea is actually listed twice, as a land snail and as a marine snail, however, it is not counted twice.

GRAND TOTAL OF MOLLUSKS, April 2017 to March 2018, 48 species

Posted on March 05, 2018 05:31 PM by susanhewitt susanhewitt | 12 observations | 4 comments | Leave a comment

February 01, 2018

Mystery of the distribution of an estuarine clam species

There is a fairly large species of obligatorily estuarine clam that lives in the Gulf of Mexico. It is edible, and it was so common there that the shells used to be crushed and used as road gravel. The scientific name of this clam is Rangia cuneata -- the Atlantic Rangia. It is not very beautiful, but it is interesting.

This clam species cannot survive in water of full ocean salinity. Adult clams can survive in freshwater, but they can't reproduce there.

During the Pleistocene period, which ended 10,000 years ago, this species lived in the Gulf of Mexico, but it also occurred in various estuaries on the East Coast of the US, from New Jersey south -- we have plenty of fossil evidence of that fact.

In 1955, an observer found a colony of this clam species living in an estuary on the East Coast. This clam species currently lives in several East Coast estuaries, including the estuary that surrounds the island where I live -- the estuary of the Hudson River. Since last April I have found about 50 valves of this species on the Harlem River beaches of Randall's Island Park, Manhattan, NYC. The salinity right there is most often between 18 and 23, but of course it can vary a lot more than that.

One theory as to how these clams ended up living in several different East Coast estuaries is the idea that they were introduced from the Gulf of Mexico by human agency -- either as larvae in ballast water, or with oysters when new oyster beds were being set up.

The other theory is that there were small relict populations of the clam that had survived in East Coast estuaries since the Pleistocene, and that these populations underwent a resurgence during and after the 1950s, and thus became noticeable where previously they were overlooked.

Currently people favor the first theory over the second one, but both ideas seem a little surprising when you think carefully about them.

For example:

1. How did the clam first spread from estuary to estuary WITHIN the Gulf of Mexico?

2. If the clam was introduced to the East Coast by humans, how come it took until 1955 to become established? There was plenty of shipping and ballast water before then.

3. In the 20th century, shell collecting was not popular as a hobby until a few years after WWII, so 1955 would have been more or less exactly the time when people would start looking for, and finding, interesting shells which might have been overlooked previously. Is this relevant?

4. How about the effect of global warming? When did ocean temperatures on the East Coast start to rise? Is that relevant?

This is a very interesting clam, and it's a bit of a puzzle too.

Posted on February 01, 2018 05:46 PM by susanhewitt susanhewitt | 6 observations | 11 comments | Leave a comment

January 21, 2018

Lots of seashells at New Haven, Connecticut!

On Friday, January 19th, 2018, a friend of mine (Charlie Whitman) drove Ed and I north from NYC to New Haven, Connecticut, to meet up with another old friend from Massachusetts (Jay Cordeiro), so that Charlie could give Jay a full set of "New York Shell Club Notes" to place in some deserving institution, since the NYC shell club is now, finally, defunct. It was a relatively nice day with temperatures in the 40s and a little sun, although there were still piles of ice around here and there, ice-covered ponds, slabs of ice on the beaches, and so on.

We all met up briefly in a small parking area not far west of the Long Wharf. Charlie and I noticed that on the shore below the rip-rap rocks there was a small sand beach with several very promising-looking full drift lines of mostly white shells. We could not spare any time to search the drift right then, because all of us except Ed and I needed to go eat at Pepe's Pizza.

However, when it was time to return to NYC, Charlie took a little detour back to Long Wharf Park, where he and I started combing the beach drift. It was now low tide and even more beach was exposed. The beach drift was far richer in species than we had imagined, so we spent almost an hour there. We also both took sediment samples home with us.

Here is what we found. The micro species are marked with an M.

Hydobia totteni -- numerous shells -- M
Littorina littorea -- several fresh shells
Littorina saxatilis -- one broken shell
Assiminea succinta -- one shell -- M
Bittium alternatum -- one broken shell -- M
Crepidula convexa -- several fresh shells
Crepidula fornicata -- live
Crepidula plana -- one shell
Neverita duplicata -- several shells
Eupleura caudata -- several shells
Urosalpinx cinerea -- several shells
Mitrella lunata -- one fresh shell -- M
Busycotypus canaliculatus -- four of them
Tritia obsoleta -- countless shells
Tritia trivittata -- some shells
Boonea sp. -- many shells -- M

Geukensia demissa -- live
Anadara ovalis -- a fragment
Anadara transversa -- one small valve
Argopecten irradians -- many fragments
Crassostrea virginica -- with flesh still inside
Mulinia lateralis -- one valve
Ensis directus --paried valves
Macoma balthica -- paired valves
Gemma gemma -- paired valves -- M
Mercenaria mercenaria -- paired valves
Petricola pholadiformis -- one valve
Mya arenaria -- paired valves

A total of 28 species of shelled mollusks! I am assuming that the drift on this little beach at Long Wharf Park is not normally so extremely rich in species -- perhaps this abundance of beach drift had something to do with the recent prolonged extreme cold snap as well as the snow storm / nor'easter that happened a couple of weeks ago.

We also found several other kinds of marine life:

Snail Fur
Atlantic Horseshoe Crab
Trumpet Worms
Bay Barnacle
Fragile Barnacle

Sea Lettuce -- Ulva lactuca

Posted on January 21, 2018 04:13 PM by susanhewitt susanhewitt | 22 observations | 9 comments | Leave a comment

January 12, 2018

Sanibel Island versus Randall's Island

In mid-December 2017, I had a 16-day trip to Sanibel Island, in Lee County, Florida on the Gulf of Mexico. It was gorgeous, and I made a lot of observations there. I also met up for three days with two other citizen scientist malacologists, although neither of them is on iNaturalist.

My husband and I came back home to two or three mild days of winter weather in NYC. Then suddenly a prolonged and extreme frigid weather spell hit New York City and the whole of the northeast and central part of the country. It was hard to get through -- even indoors with steam heat it was cold.

But that eased up recently, and I was able to get back to Randall's Island, which is currently my favorite local iNat destination.

I am not a birder, but I managed to see Red-breasted Mergansers for the first time on Sanibel, and then saw some a couple days ago on Randall's!

As usual, I am shelling a lot on both islands, but I try to record as many other species of organisms as I reasonably can.

You would not think that Sanibel and Randall's have much in common at all, but surprisingly, seven marine mollusk species which are present on Sanibel are also present on Randall's! They are: the Hard Clam, the Atlantic Bay Scallop, the Common Oyster, the Dwarf Surf Clam, the Angel Wing (I found one fragment of a valve on Randalll's), the Eastern Melampus, and the Shark Eye.

One really interesting thing about the beaches on Randall's Island is that you can find valves of the Atlantic Rangia there, an estuarine species. But that is another story all by itself!

I love iNaturalist!

Posted on January 12, 2018 05:38 PM by susanhewitt susanhewitt | 20 observations | 6 comments | Leave a comment

September 30, 2017

Lucky me -- iNatting in Southern California

It was great to see @finatic and @jaykeller again! They were kind enough to take me iNatting in the Tijuana River Valley and in Border Field State Park, both of which were wonderfully atmospheric places -- like going back in time to the Old West.

On my final weekend, finatic drove me to Mission Trails Regional Park (a terrific wilderness area) and to a canyon in La Jolla, where we met up with jaykeller. On that trip we were joined by @cedric_lee and @alex_bairstow. We walked, and then hiked, and then pushed our way through the vegetation as far up into the canyon as it was possible to go without using machetes. We saw a lot of interesting organisms, but we failed to find the small native land snail species that was recorded there back in 1953.

Alex had previously gone beachcombing with me at Cardiff Reef, where he had demonstrated his sharp eyesight and an impressive knowledge of the local shelled marine mollusk fauna, especially considering he had only started learning to identify them the previous fall.

Thank you BJ and Jay! Apart from everything else which was great to see and learn, it was fascinating for me to be introduced to three species of native Californian land snails -- extraordinary survivors in the chaparral, which is a very dry shrub landscape that most of the time is only moistened on-and-off by sea fog at night.

I relentless picked the brains of those around me -- and in a few days I learned more about Southern Californian natural history than I have done in the previous 40 years. Wonderful!

Posted on September 30, 2017 12:13 PM by susanhewitt susanhewitt | 16 observations | 3 comments | Leave a comment