Retention of Marks and Their Effects on Growth, Behavior, and Migrations of the American lobster, Homarus americanus
- 1 April 1970
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 99 (2) , 409-417
- https://doi.org/10.1577/1548-8659(1970)99<409:romate>2.0.co;2
Abstract
Laboratory and field experiments were conducted with the lobster, Homarus americanus, to test the retention through molting of three primary marks—the back tag, elbow tag, and brand. Relatively more back tags were retained through the molt than elbow tags or brands. Molestation among tagged lobsters contributed significantly to tag loss. In November 1965 and July 1966, a total of 1776 lobsters were tagged and released at Monhegan Island, Maine. Lobsters were given a primary mark plus a secondary mark of amputated abdominal scutes and spines. The secondary mark was retained through 2 molts and permitted recognition of a lobster that had lost its primary mark. The recapture of marked lobsters through June 1968 yielded information on tag retention and the effects of marks on growth and behavior. Lobsters marked with the back tags had an 88% retention rate through a molt compared with 55% for brands and 16% for elbow tags. By June 1968 approximately 98% and 77% of the November release of back‐tagged and elbow‐tagged lobsters had been recovered compared with 32% and 12% for the July release. Similar estimates for branded lobsters are not available since branding did not permit recognition of large numbers of individuals. Growth increments in carapace length were normal for back‐tagged (11.0 mm) and elbow‐tagged (10.8 mm) lobsters and below normal for branded lobsters (7.2 mm). Incidence of shedding by 10 mm size groups appeared normal for back‐tagged lobsters and less than normal for elbow‐tagged lobsters. Similar estimates for branded lobsters are not available since carapace lengths at the time of branding could not be determined for lobsters that had shed. Marked lobsters released in November appeared normal in their search for burrows and in their interactions with unmarked individuals of the population. One‐third of the lobsters marked in July with the back tag and elbow tag lost their equilibrium for periods up to 3 hours immediately after tagging. Branded lobsters appeared normal immediately after branding. Movements of marked lobsters appeared normal. Ninety‐nine percent of the recoveries were taken within the 2‐mile fishing limit of Monhegan Island. The rest were taken 4 to 20 miles northeast to northwest of the island.This publication has 0 references indexed in Scilit: