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Didemnum sp. - Sandwich, Massachusetts, Images


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NEW ENGLAND COAST LINKS: Occurrences / Location Data / Regional Location Map
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MAINE IMAGES: Cobscook Bay, ME /   Cobscook Bay2, ME /   Estes Head, ME /   Fort Island Narrows, ME /   Thrumcap Island, ME /   Long Island Ledges, ME  /   Wentworth Point, ME
MASSACHUSETTS IMAGES: Boston Harbor, MA /   Chatham,  MA /   Oak Bluffs, MA /   Orleans, MA /   Osterville Grand Island, MA /   Provincetown, MA /   Sandwich, MA /   Sandwich Town Beach, MA /   Sandy Bay, MA /   Stage Harbor, MA /   Strong Island, MA /   Vineyard Haven, MA /   Wellfleet Harbor, MA /   West Falmouth Harbor, MA /   Woods Hole (Eel Pond), MA /   Woods Hole (Iselin Dock), MA
NEW HAMPSHIRE IMAGES: Fort Point, NH /  New Castle Island, NH /  Piscataqua River, NH
RHODE ISLAND IMAGES: Beavertail Point, RI /   Fort Wetherill, RI  /   Narragansett, RI
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June 03  /  4 Dec. 03  /  3 Feb. 04  /  4 Oct. 04

October 4, 2004

Click here for video of Didemnum sp. in tide pool at Sandwich, Massachusetts.		 Video imagery DB_STP_MAvideo2. Tunicate colonies of Didemnum sp. encrusting cobbles boulders and macro algae; shows typical colony growth upward from base of cobbles and boulders; also shows degenerating colony peeling off rock and being grazed by periwinkles (Littorina littorea). Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Video recorded at low tide. October 4, 2004. Video credit: Dann Blackwood (USGS). Location no. 1.
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June 2003
Image MC_STP_03, tunicate colonies of D. sp. in early stage of invasion of the Sandwich tide pool.
Image MC_STP_03		 Image MC_STP_03. Tunicate colonies of Didemnum sp. in early stage of invasion of the Sandwich tide pool. D. sp. colonies are encrusting a boulder and overgrowing colonies of Botryllus schlosseri (dark green) and Botrylloides violaceus (small dark yellow colony in right center of the image). Boulder was lifted out of the water for photo; tunicate colonies are contracted. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. June, 2003. Collector: Mary Carman. Photo credit: Mary Carman, WHOI. Location no. 1.
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December 4, 2003
View of the Sandwich tide pool on the south side of the east entrance of the Cape Cod canal.
View of the Sandwich tide pool on the south side of the east entrance of the Cape Cod canal.		 Image DB_STP_DSC0161. View of the Sandwich tide pool on the south side of the east entrance of the Cape Cod canal at low tide, looking east. Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSC0132, tunicate colonies of the D. sp. encrusting boulders, dark red algae, and the surrounding gravel seabed.
Image DB_STP_DSC0132		 Image DB_STP_DSC0132. Tunicate colonies of Didemnum sp. encrusting boulders, dark red algae, and the surrounding gravel seabed. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSC0146, tunicate colonies of the D. sp. encrusting a boulder and overgrowing dark red algae and pink calcareous algae.
Image DB_STP_DSC0146		 Image DB_STP_DSC0146 Tunicate colonies of Didemnum sp. encrusting a boulder and overgrowing dark red algae and pink calcareous algae. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSC0149, tunicate colonies of the D. sp. advancing over a boulder surface and overgrowing barnacles and a green encrusting sponge.
Image DB_STP_DSC0149		 Image DB_STP_DSC0149 Tunicate colonies of Didemnum sp. advancing over a boulder surface and overgrowing barnacles and a green encrusting sponge (cf. Halichondria sp.). Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSC0155, tunicate colonies of the D. sp. advancing up the side of a boulder and overgrowing barnacles, green algae, and dark red algae.
Image DB_STP_DSC0155		 Image DB_STP_DSC0155 Tunicate colonies of Didemnum sp. advancing up the side of a boulder and overgrowing barnacles, green algae, and dark red algae. D. sp. is exposed here at low tide. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1840, tunicate colonies of the D. sp. encrusting the surface of a boulder and enveloping dark red algae.
Image DB_STP_DSCN1840		 Image DB_STP_DSCN1840 Tunicate colonies of Didemnum sp. encrusting the surface of a boulder and enveloping dark red algae. Note contrasting smooth and appendaged surfaces of the tunicate. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4 , 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1843, tunicate colonies of the D. sp. overgrowing dark green algae (rockweed) attached to a boulder.
Image DB_STP_DSCN1843		 Image DB_STP_DSCN1843 Tunicate colonies of Didemnum sp. overgrowing dark green algae (rockweed) attached to a boulder. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1846, tunicate colonies of the D. sp. overgrowing dark red algae and green encrusting sponge attached to a boulder.
Image DB_STP_DSCN1846		 Image DB_STP_DSCN1846 Tunicate colonies of Didemnum sp. overgrowing dark red algae and green encrusting sponge attached to a boulder. Note contrasting smooth and appendaged surfaces of the tunicate. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1847, tunicate colonies of the D. sp. overgrowing dark green and dark red algae attached to a boulder.
Image DB_STP_DSCN1847		 Image DB_STP_DSCN1847 Tunicate colonies of Didemnum sp. overgrowing dark green and dark red algae attached to a boulder. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1848, tunicate colonies of the D. sp. growing out from the side of a boulder and displaying ropey or bearded morphology; and advancing over the adjacent seabed and displaying typical pancake batter morphology.
Image DB_STP_DSCN1848		 Image DB_STP_DSCN1848 Tunicate colonies of Didemnum sp. growing out from the side of a boulder and displaying "ropey or bearded" morphology; and advancing over the adjacent seabed and displaying typical "pancake batter" morphology. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1852, tunicate colonies of the D. sp. growing on the sides of a boulder and beginning to display ropey or bearded morphology; and advancing over the adjacent seabed and displaying typical pancake batter morphology.
Image DB_STP_DSCN1852		 Image DB_STP_DSCN1852 Tunicate colonies of Didemnum sp. growing on the sides of a boulder and beginning to display "ropey or bearded" morphology; and advancing over the adjacent seabed and displaying typical "pancake batter" morphology. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1854, tunicate colonies of D. sp. encrusting the side of a boulder and overgrowing dark red algae.
Image DB_STP_DSCN1854		 Image DB_STP_DSCN1854 Tunicate colonies of Didemnum sp. encrusting the side of a boulder and overgrowing dark red algae. Note the contrasting "ropey" morphology on the boulder and the smooth morphology on the seabed below. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1856, tunicate colonies of the D. sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae.
Image DB_STP_DSCN1856		 Image DB_STP_DSCN1856 Tunicate colonies of Didemnum sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1857,Tunicate colonies of the Didemnum sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae.
Image DB_STP_DSCN1857		 Image DB_STP_DSCN1857 Tunicate colonies of Didemnum sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae. Close up of Image DB_STP_DSCN1856. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1858, tunicate colonies of D. sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae.
Image DB_STP_DSCN1858		 Image DB_STP_DSCN1858 Tunicate colonies of Didemnum sp. encrusting the sides of two boulders and overgrowing dark green and dark red algae. Close up of Image DB_STP_DSCN1856. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1859, tunicate colonies of the D. sp. overgrowing dark green algae and displaying a ropey surface.
Image DB_STP_DSCN1859		 Image DB_STP_DSCN1859 Tunicate colonies of Didemnum sp. overgrowing dark green algae and displaying a "ropey" surface. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1860, tunicate colonies of the D. sp. overgrowing dark green algae and developing a surface.
Image DB_STP_DSCN1860		 Image DB_STP_DSCN1860 Tunicate colonies of Didemnum sp. overgrowing dark green algae and developing a "ropey" surface. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1862, tunicate colonies of the D. sp. encrusting the sides of boulders and overgrowing dark red and dark green algae.
Image DB_STP_DSCN1862		 Image DB_STP_DSCN1862. Tunicate colonies of Didemnum sp. encrusting the sides of boulders and overgrowing dark red and dark green algae. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1864, tunicate colonies of the D. sp. encrusting the sides of a boulder, overgrowing dark red algae, and beginning to advance over the adjacent seabed.
Image DB_STP_DSCN1864		 Image DB_STP_DSCN1864 Tunicate colonies of Didemnum sp. encrusting the sides of a boulder, overgrowing dark red algae, and beginning to advance over the adjacent seabed. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1866, tunicate colonies of the D. sp. advancing over a boulder surface and overgrowing barnacles and a green encrusting sponge.
Image DB_STP_DSCN1866		 Image DB_STP_DSCN1866. Tunicate colonies of Didemnum sp. advancing over a boulder surface and overgrowing barnacles and a green encrusting sponge (cf. Halichondria sp.). Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
Click here to download image.
Image DB_STP_DSCN1871, tunicate colonies of the D. sp. on the side of a boulder and overgrowing a green encrusting sponge.
Image DB_STP_DSCN1871		 Image DB_STP_DSCN1871. Tunicate colonies of Didemnum sp. on the side of a boulder and overgrowing a green encrusting sponge (cf. Halichondria sp.). Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Tunicate colonies of the Didemnum sp. encrusting the side of a boulder and showing the transition from the morphology on the boulder side to the smooth morphology on the seabed below.
Image DB_STP_DSCN1872		 Image DB_STP_DSCN1872. Tunicate colonies of Didemnum sp. encrusting the side of a boulder and showing the transition from the "ropey" morphology on the boulder side to the smooth morphology on the seabed below. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
Click here to download image.
Image DB_STP_DSCN1880, tunicate colonies of the D. sp. overgrowing the fronds of dark green algae.
Image DB_STP_DSCN1880		 Image DB_STP_DSCN1880. Tunicate colonies of Didemnum sp. overgrowing the fronds of dark green algae. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1885, tunicate colonies of the D. sp. encrusting the side of a boulder and overgrowing dark red algae.
Image DB_STP_DSCN1885		 Image DB_STP_DSCN1885. Tunicate colonies of Didemnum sp. encrusting the side of a boulder and overgrowing dark red algae. Note the red colony of the tunicate Botrylloides violaceus. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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Image DB_STP_DSCN1894, tunicate colonies of the D. sp. growing on the sides of a boulder and beginning to display morphology; and advancing over the adjacent seabed and displaying typical morphology.
Image DB_STP_DSCN1894		 Image DB_STP_DSCN1894. Tunicate colonies of Didemnum sp. growing on the sides of a boulder and beginning to display "ropey or bearded" morphology; and advancing over the adjacent seabed and displaying typical "pancake batter" morphology. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
Click here to download image.
Image DB_STP_DSCN1901, tunicate colonies of the D. sp. growing on the side of a boulder and overgrowing red and green encrusting sponges.
Image DB_STP_DSCN1901		 Image DB_STP_DSCN1901. Tunicate colonies of Didemnum sp. growing on the side of a boulder and overgrowing red and green (cf. Halichondria sp.) encrusting sponges. The leading edge of the tunicate colony is beginning to peel away from the upper edge of the boulder. Note the small colonies of D. sp. beginning to grow on the upper surface of the boulder. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Collected at low tide. December 4, 2003. Collectors: Mary Carman and Page Valentine. Photo credit: Dann Blackwood, U.S. Geological Survey. Location no. 1.
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February 3, 2004
View of the Sandwich tide pool on the south side of the east entrance of the Cape Cod canal.
Image DB_STP_DSC0090		 Image DB_STP_DSC0090. View of the Sandwich tide pool on the south side of the east entrance of the Cape Cod canal at low tide, looking east (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal, 11 foot (3.4 m) range. Water temperature 1 deg C. Observed at low tide. February 3, 2004. Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2010, Tunicate colonies of D. sp. encrusting a boulder and being preyed upon by the common periwinkle.
Image DB_STP_DSCN2010		 Image DB_STP_DSCN2010. Tunicate colonies of Didemnum sp. encrusting a boulder and being preyed upon by the common periwinkle, Littorina littorea. Note that the snails are numbered for comparison with the following images. Elliptical and subcircular holes in D. sp. are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2011, tunicate colonies of D. sp. encrusting a boulder and being preyed upon by the common periwinkle.
Image DB_STP_DSCN2011		 Image DB_STP_DSCN2011. Tunicate colonies of Didemnum sp. encrusting a boulder and being preyed upon by the common periwinkle, Littorina littorea. Snail no. 1 has been removed to show area grazed through the D. sp. colony. Elliptical and subcircular holes in D. sp. are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
Click here to download image.
Image DB_STP_DSCN2012, tunicate colonies of D. sp. encrusting a boulder and being preyed upon by the common periwinkle.
Image DB_STP_DSCN2012		 Image DB_STP_DSCN2012. Tunicate colonies of Didemnum sp. encrusting a boulder and being preyed upon by the common periwinkle, Littorina littorea. Snails no. 1, 2 and 3 have been removed to show areas grazed through the D. sp. colony. Elliptical and subcircular holes in D. sp. are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2015, tunicate colonies of D. sp. encrusting a boulder and being preyed upon by the common periwinkle.
Image DB_STP_DSCN2015		 Image DB_STP_DSCN2015. Tunicate colonies of Didemnum sp. encrusting a boulder and being preyed upon by the common periwinkle, Littorina littorea. Snails no. 1-6 have been removed to show grazed areas in the D. sp. colony. Snails 1-3 have grazed through the tunicate, snail no. 4 has grazed the surface of the colony, and snails 5 and 6 were grazing the edges of a large hole in the colony when they were removed. Elliptical and subcircular holes in D. sp. are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSC0089, dead tunicate colonies of D. sp. peeling away from the top of a boulder exposed at low tide.
Image DB_STP_DSC0089		 Image DB_STP_DSC0089. Dead tunicate colonies of Didemnum sp. peeling away from the top of a boulder exposed at low tide. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN1994, dying tunicate colony of D. sp. beginning to peel away from a boulder.
Image DB_STP_DSCN1994		 Image DB_STP_DSCN1994. Dying tunicate colony of Didemnum sp. beginning to peel away from a boulder. Colony surface shows a yellow discoloration; small dark spots are clusters of fecal pellets showing through the tunic. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN1998, dying tunicate colony of D. sp. peeling away from the side of a boulder.
Image DB_STP_DSCN1998		 Image DB_STP_DSCN1998. Dying tunicate colony of Didemnum sp. peeling away from the side of a boulder. Colony surface shows onset of yellow discoloration; small dark spots are clusters of fecal pellets showing through the tunic. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN1999, dying tunicate colony of D. sp. peeling away from the side of a boulder.
Image DB_STP_DSCN1999		 Image DB_STP_DSCN1999. Dying tunicate colony of Didemnum sp. peeling away from the side of a boulder. Close-up of Image DB_STP_DSCN1998 showing ragged edge of colony with elliptical holes interpreted to represent areas that have been grazed by the common periwinkle Littorina littorea. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS).Location no. 1.
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Image DB_STP_DSCN2003, dying tunicate colony of D. sp. peeling away from a boulder, exposing the underside of the colony.
Image DB_STP_DSCN2003		 Image DB_STP_DSCN2003. Dying tunicate colony of Didemnum sp. peeling away from a boulder, exposing the underside of the colony, which is being preyed upon by the common periwinkle, Littorina littorea. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS).Location no. 1.
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Image DB_STP_DSCN2001, dying tunicate colony of D. sp. encrusting the side of a boulder.
Image DB_STP_DSCN2001		 Image DB_STP_DSCN2001. Dying tunicate colony of Didemnum sp. encrusting the side of a boulder. Colony surface shows a yellow discoloration; small dark spots are clusters of fecal pellets showing through the tunic. This colony shows little predation by the common periwinkle, Littorina littorea. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2019, dying tunicate colony of D. sp. encrusting the side of a boulder.
Image DB_STP_DSCN2019		 Image DB_STP_DSCN2019. Image DB_STP_DSCN2019. Dying tunicate colony of Didemnum sp. encrusting the side of a boulder. Colony surface shows a yellow discoloration; small dark spots are clusters of fecal pellets showing through the tunic. D. sp. is being preyed upon by the common periwinkle, Littorina littorea. Elliptical and subcircular holes in the tunicate colony are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN1995, dying tunicate colony of D. sp. encrusting the side of a boulder.
Image DB_STP_DSCN1995		 Image DB_STP_DSCN1995. Dying tunicate colony of Didemnum sp. encrusting the side of a boulder. Colony surface shows a yellow discoloration; small dark spots are clusters of fecal pellets showing through the tunic. D. sp. is being preyed upon by the common periwinkle, Littorina littorea. Elliptical and subcircular holes in the tunicate colony are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2006, dying tunicate colony of D. sp. encrusting the sides of boulders.
Image DB_STP_DSCN2006		 Image DB_STP_DSCN2006. Dying tunicate colony of Didemnum sp. encrusting the sides of boulders. Small dark spots on the surface of the colonies are clusters of fecal pellets showing through the tunic. D. sp. is being preyed upon by the common periwinkle, Littorina littorea. Elliptical and subcircular holes in the tunicate colony are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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Image DB_STP_DSCN2020, tunicate colony of D. sp. encrusting a boulder and being preyed upon by the common periwinkle.
Image DB_STP_DSCN2020		 Image DB_STP_DSCN2020. Tunicate colony of Didemnum sp. encrusting a boulder and being preyed upon by the common periwinkle, Littorina littorea. Dark spots on the surface of the colony are clusters of fecal pellets showing through the tunic. At least 20 snails are present in the image Elliptical and subcircular holes in D. sp. are interpreted to represent areas that have been grazed by the periwinkles. Sandwich tide pool (41 deg 46.42 min N lat, 70 deg 29.30 min W lon). Water depth, intertidal range to 11 feet (3.4 m). Water temperature 1 deg C. Observed at low tide. February 3, 2004. Observers: Page Valentine (USGS) and Mary Carman (WHOI). Photo credit: Dann Blackwood (USGS). Location no. 1.
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NEW ENGLAND COAST LINKS: Occurrences / Location Data / Regional Location Map
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MAINE IMAGES: Cobscook Bay, ME /   Cobscook Bay2, ME /   Estes Head, ME /   Fort Island Narrows, ME /   Thrumcap Island, ME /   Long Island Ledges, ME  /   Wentworth Point, ME
MASSACHUSETTS IMAGES: Boston Harbor, MA /   Chatham,  MA /   Oak Bluffs, MA /   Orleans, MA /   Osterville Grand Island, MA /   Provincetown, MA /   Sandwich, MA /   Sandwich Town Beach, MA /   Sandy Bay, MA /   Stage Harbor, MA /   Strong Island, MA /   Vineyard Haven, MA /   Wellfleet Harbor, MA /   West Falmouth Harbor, MA /   Woods Hole (Eel Pond), MA /   Woods Hole (Iselin Dock), MA
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RHODE ISLAND IMAGES: Beavertail Point, RI /   Fort Wetherill, RI  /   Narragansett, RI
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