Life in the Pile Fields

Hudson River Park Trust 353 West St. Pier 40, 2nd Floor NY, NY 10014 Andrew M. Cuomo, Governor Bill de Blasio, Mayor Gale A. Brewer, Manhattan Borough President Diana L. Taylor, Chair Madelyn Wils, President & CEO hudsonriverpark.org About Pile Fields: Hudson A Vertical River Park Community

Hudson River Park is a 550-acre park and Estuarine Nearly half of the entire Hudson River is a tidal estuary Sanctuary from Chambers Street to W 59 Street in due to the daily flow of salty ocean water mixing with Manhattan. It includes four miles of waterside esplanade, upstream fresh water sources. Estuaries, like the Park’s 16 reconstructed public piers to date, four dedicated sanctuary waters, are among the most productive boat houses for sailing, rowing and paddling, and ecosystems on earth. Park waters support a dynamic numerous other places to play, learn and relax. The Park underwater world and provide essential habitat for more offers hands-on education and interactive scientific than 70 different species of fish. research with the purpose of communicating the ecological importance of the Park’s 400-acre Estuarine Hudson River Park’s pile fields are clusters of aging Sanctuary. Through parkwide programs, visitors are wooden fragments that remain from bygone piers. The invited to experience the River as a living laboratory for Park’s pile fields are some of the most notable elements community engagement and stewardship. of Hudson River Park’s Estuarine Sanctuary because of the dynamic habitat that they create and the complex food web they support. Explore a Dynamic 18. Double-crested cormorant Underwater World

1. Algae such as sea lettuce, Ulva lactuca, and red 10. Blue mussels Mytilus edulis, use byssal threads algae, Ceramium tenuicorne, are marine plants that (strong thread-like anchors) to attach themselves onto need sunlight to grow. They often use holdfasts (root- surfaces including piles. These threads can detach to Spray Zone like anchors) to attach to piles and provide much help mussels mobilize for food and protection. This transitional area is needed food and shelter. where water meets air. High 6. Mallard ducks 11. Oysters Crassostrea virginica, were once tides, heavy wave activity 2. Plankton are often-microscopic plants and abundant in New York Harbor, and now are a rare and storm events bring moisture to this zone. 4. Gribbles animals float with moving water. Plant plankton sight today due to centuries of overharvesting and are phytoplankton and animal plankton are water pollution. A single oyster can filter 50 gallons zooplankton. Plankton are the foundation of the of water each day, removing pollutants and improving Hudson River food web. water quality. Intertidal Zone 3. Naval shipworms Teredo navalis, are elongated 12. Comb jellies Mnemiopsis leidyi, are translucent This dynamic area is mollusks that bore into submerged wood with a invertebrates with rows of combs (tiny hairs) which submerged during high tide 1. Algae 2. Plankton 14. Atlantic silversides and exposed at low tide. helmet-like shell leaving behind numerous habitat run up and down their bodies. These combs act like Organisms that live in this 5. Barnacles nooks throughout an aging pile. oars to propel the jellies vertically as they float with zone can withstand extreme tidal changes, wave action tides and currents. and temperature variations. 4. Gribbles Limnoria tripunctata, are isopods, a class of crustaceans (shelled animals) with segmented 13. Lined seahorses Hippocampus erectus, are bodies. Their stomachs contain a special enzyme that weak swimmers due to their vertical orientation and 10. Blue mussels allows them to digest wood. small dorsal fin. For support against river currents, Subtidal Zone they use their curled tail to grasp onto piles. 5. Barnacles Amphibalanus improvisus, undergo Almost always submerged a complete metamorphosis when their free-floating 14. Atlantic silversides Menidia menidia, swim in in water, this zone is 17. Striped bass dominated by various fish larvae cement themselves to piles and grow shells. large schools for protection from predators. They species, plants and sessile Their shell closes at low tide to avoid drying out, and use an extra sensory organ called a lateral line organisms that benefit from instinctively reopens at high tide, allowing them to to coordinate and detect movements by feeling the sunlight above. feed with their feathery legs. vibrations in the water. 3. Naval shipworms 6. Mallard ducks Anas platyrhynchos, are 15. Blue crabs have the scientific name Callinectes 13. Lined seahorse dabblers—they tip forward in the water to graze on sapidus, which translates to “beautiful, tasty 9. Sponges plants beneath the surface. Females are mottled swimmer” because they glide with two back legs brown, a physical quality that provides ideal shaped as paddles. They can also release and regrow camouflage for guarding a nest. their legs when threatened.

7. Sea squirts 7. Sea squirts Molgula manhattensis, are small 16. Oyster toadfish Opsanus tau, can survive in 12. Comb jellies tubular animals that resemble a grape. As larvae, they poor river conditions because of their tolerance to swim freely before transforming into a sessile (non- pollution. They croak loudly when agitated or trying moving) adult. They have two siphons that they use to attract a mate. to filter water. 11. Oysters 17. Striped bass Morone saxatilis, begin their lives 8. Grass shrimp Palaemonetes pugio, have small as eggs in the Hudson River’s fresh water and spend translucent bodies that reveal their inner anatomy, their adult years in the Atlantic Ocean. As juveniles, Benthic Zone 8. Grass shrimp notably showcasing a female’s eggs during spawning they spend a few years in estuary waters, especially season. A powerful flick of their muscular tail allows near and in the protective pile fields. The bottom of the river them to move quickly through the water. is made up of rocks, mud and clay. Strong tides and 18. Double-crested cormorants Phalacrocorax currents in the Hudson 9. Sponges such as red beard sponges, Microciona auritus, can often be found in the pile fields with their River move this sediment, prolifera, grow on wooden piles, rocks, and other hard wings spread out to dry. Unlike other water birds, they contributing to the water's brownish hue. surfaces and create habitat for small animals. Boring lack waterproof oil on their feathers allowing them to sponges, Cliona celata, drill holes into mollusk shells dive to impressive depths. to anchor themselves. This eventually kills the mollusk and allows the sponges to expand their colony. 15. Blue crab 16. Oyster toadfish Plankton Striped Bass Copepoda Morone saxilitis

Plankton are responsible for providing food and Juvenile striped bass live in the Park’s pile fields oxygen to a variety of organisms, making them where waves are gentle and small critters to eat the foundation of the food web. are plentiful.

Naval Shipworms Oyster Toadfish Teredo navalis Opsanus tau

Naval shipworms and gribbles bore into wooden Oyster toadfish blend into the piles at the river piles, creating crevices where other aquatic plants bottom where they ambush small crabs, shrimp, and animals take hold. snails, mussels and fish.

Red Beard Sponge Blue Crab Microciona prolifera Callinectes sapidus

Red beard sponges and other aquatic species Blue crabs are pile field predators that use their attach themselves to piles, offering food and claws to tear food, which sometimes includes other shelter to mobile animals. blue crabs.

Barnacles Mallard Ducks Amphibalanus improvisus Anas platyrhychos

Barnacles are crustaceans that permanently Mallard ducks swim through the piles, skimming the affix to piles, an ideal location to filter feed on water’s surface for algae and invertebrates to eat. detritus.

Oysters Double-Crested Crassostrea virginica Cormorant Phalacrocorax auritus Oysters attach to piles in clusters, building habitat for other animals and decreasing wave Double-crested cormorants can often be seen energy during storms. drying their feathers atop the piles and diving for fish in the river below.