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Arenicola marina. DESCRIPTIVE INFORMATION Segmented worms burrowing in littoral zones Digs tunnels in ground with length ±50 cm (depends on body length) Can make up to 30% of biomass in an average sandy beach (important part of food web in their habitat)
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Arenicola marina • DESCRIPTIVE INFORMATION • Segmented worms burrowing in littoral zones • Digs tunnels in ground with length ±50 cm (depends on body length) • Can make up to 30% of biomass in an average sandy beach (important part of food web in their habitat) • Avoids predation: tail can be reground if eaten Tyler-Walters, H., 2007. Arenicola marina. Blow lug. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25/03/2008].
Arenicola marina ECOLOGY Swallows ground (containing nutrients) as it burrows which passes rapidly through its intestine Feeds on organic materials such as microorganisms & detritus present in the sediment Statocysts allow animal to burrow head down and position itself correctly for feeding
Arenicola marina HABITAT • Inhabitant of the littoral • Found on mid to lower shores in sand & muddy sand & in sheltered sediment • At low tide the oxygen content in burrows are about 3 times lower than in high tide • Fluctuations in salinity, temperature & oxygen supply due to duration of exposure to surface Arenicola marina, Lugworm - MarineBio.org. Retrieved Friday, April 4, 2008, from http://marinebio.org/species.asp?id=57.
Methods to determine population size • Quadrat method: Transects of 10 square meters at random spots. Cores of transects taken, sieved & sorted in the laboratory. Amounts for lugworm for each transect are listed. The mean (average) calculated to determine an estimate of population size per square meter. • Mark-recapture method: captures group of individuals, each are marked with an identifier & released back into the environment. Enough time passes for the marked ones to be distributed among the unmarked ones. Go back to capture again each time & keep record of marked & unmarked. The captures are analyzed mathematically to determine population size
Arenicola marina REFERENCES • Biology Bulletin, July 2003, Vol 30, No 4, Pgs 411-418, MAIK Nauka/Interperiodica • Marine Ecology Progress Series, 1994, Vol 115, Pgs 139-149 • http://marinebio.org/species.asp?id=57 • Tyler-Walters, H., 2007. Arenicola marina. Blow lug. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 25/03/2008]. Available from: