Mollusks from Randall's Island, an update

RANDALL’S ISLAND, MANHATTAN, NYC, US
MOLLUSKS

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.

[NOTE: Two recent additions are in capital letters]

PART I - MARINE/ESTUARINE MOLLUSKS
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MARINE AND ESTUARINE BIVALVES:

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
TAGELUS PLEBEIUS, STOUT TAGELUS -- ENTIRE SHELL OF JUVENILE
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

MARINE GASTROPODS: 

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.
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RANDALL’S ISLAND MOLLUSKS - PART II - FRESHWATER & LAND

FRESHWATER GASTROPODS:

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

LAND GASTROPODS, SNAILS AND SLUGS:

Cepaea nemoralis, Grove Snail -- many colonies
Deroceras reticulatum, Milky Slug -- several live
Deroceras sp., -- few
Oxychilus draparnaudi, Draparnaud’s Glass-snail -- live
VALLONIA COSTATA, RIBBED GRASS-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
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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 by susanhewitt susanhewitt, March 05, 2018 17:31

Observations

Photos / Sounds

Square

What

Eastern Oyster Crassostrea virginica

Observer

susanhewitt

Date

February 26, 2018 01:13 PM EST

Photos / Sounds

What

Threeline Mudsnail Tritia trivittata

Observer

susanhewitt

Date

February 26, 2018 01:41 PM EST

Description

I was excited to find this!

Photos / Sounds

What

Common Periwinkle Littorina littorea

Observer

susanhewitt

Date

February 26, 2018 02:23 PM EST

Description

This is the first time I have found one on these on this little beach, even though we already know it occurs on the rocky south end of the island, and also on the rocks in the northwest corner of the island.

Photos / Sounds

Square

What

Shipworms Family Teredinidae

Observer

susanhewitt

Date

February 27, 2018 01:42 PM EST

Photos / Sounds

What

Soft-shelled Clam Mya arenaria

Observer

susanhewitt

Date

February 27, 2018 01:42 PM EST

Photos / Sounds

Square

What

Northern Quahog Mercenaria mercenaria

Observer

susanhewitt

Date

February 27, 2018 02:22 PM EST

Photos / Sounds

Square

What

Dwarf Surfclam Mulinia lateralis

Observer

susanhewitt

Date

February 27, 2018 02:28 PM EST

Photos / Sounds

Square

What

Atlantic Jackknife Ensis leei

Observer

susanhewitt

Date

February 27, 2018 02:29 PM EST

Photos / Sounds

Square

What

Northern Dwarf-Tellin Ameritella agilis

Observer

susanhewitt

Date

February 27, 2018 02:31 PM EST

Photos / Sounds

Square

What

Solitary Glassy-Bubble Haminella solitaria

Observer

susanhewitt

Date

February 27, 2018 02:50 PM EST

Description

In this shot you can see the spiral lines on the shell.

Photos / Sounds

Square

What

Glossy Pillar Cochlicopa lubrica

Observer

susanhewitt

Date

March 3, 2018 11:41 AM EST

Description

The shell on the right is Cochlicopa lubrica. The one on the left is Discus rotundatus:

https://www.inaturalist.org/observations/10068249

Photos / Sounds

What

Chestnut Clam Astarte castanea

Observer

susanhewitt

Date

March 3, 2018 01:05 PM EST

Description

Today I found this valve, which was lying on top of some bare earth, along with a couple other shell fragments (what appeared to be a piece of Mya arenaria and a piece of a mytilid species), at the northeast corner of the Little Hell Gate Salt Marsh. The day before in NYC we had extremely heavy rains and winds, plus earth had been moved around in this small area because of some construction near there.

I am not sure how this valve came to be here. Little Hell Gate was originally a fast moving estuarine waterway that separated Wards Island from Randall's Island. This valve could, in theory, date from before Little Hell Gate was filled in during Robert Moses's reign. But I am not sure whether this clam could ever have lived in an estuarine environment because it basically likes the open coast, although it has been recorded from Long Island Sound.

A bit of a mystery. I don't think this is considered to be a food species or a bait species so it seems not very likely that this was brought here by human agency, although really it is hard to be sure one way or the other.

Comments

Thumb

Good observing and you are getting me inspired to write some posts.

Posted by brewbooks over 3 years ago (Flag)
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Thanks! Posts are fun I think.

Posted by susanhewitt over 3 years ago (Flag)
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A new addition to the list of marine bivalves! On June 23rd when Chris Girgenti and I were leading the public event "Small World" on Randall's Island, Chris picked up a small example of Tagelus plebeius on the little beach on Wards Island.

Cool!

https://www.inaturalist.org/observations/13707303

Posted by susanhewitt about 3 years ago (Flag)
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A new addition to the list of land snails: on June 16th when I was at Randall's Island with Matt Parr, in the Little Hell Gate Salt marsh we found Vallonia eccentrica, a micro land snail addition to the list:

https://www.inaturalist.org/observations/13503683

Posted by susanhewitt about 3 years ago (Flag)

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