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Fishery Bulletin 104(2) 



tions are time-intensive and marks often 

 become difficult to discern after several 

 months. Also, sea cucumbers could not be 

 located soon after release in some follow- 

 up investigations. 



Yanagisawa (1995) successfully used 

 a hot wire to brand the sea cucumber 

 Stichopiis japonicus. Although most of the 

 marked juveniles could be distinguished 

 three months later, it seemed to be difficult 

 to discern their marks after four months. 



The results of previous worldwide sea 

 cucumber tagging studies vary in success 

 by species, investigator, and location. It 

 is also possible that the technique varied 

 significantly for studies involving the same 

 styles of tagging. Therefore, the conclusions 

 of these previous tagging studies may not 

 be applied to the sea cucumber population 

 off Maine. Factors such as dermal thick- 

 ness and seasonal fluctuations likely alter 

 the capacity of the sea eumcumber to re- 

 tain tags. 



The objective of this study was to ascer- 

 tain whether a reliable means of tagging 

 the Maine sea cucumber could be identified. 

 Tagged animals would provide information 

 on growth and movement for later stud- 

 ies. This important biological information 

 would be critical for sea cucumber stock 

 assessment and management. 



Materials and methods 



The study was carried out between April and Septem- 

 ber 2003 to determine the effectiveness of various tags. 

 Initially, animals were tested by using 1) long and short 

 double T-bar tags inserted with a tagging gun; 2) dart 

 tags; 3) streamer tags; and 4) cinch-up tags. A control 

 group was also included in which animals were punc- 

 tured with the tagging gun to observe any mortality 

 from the piercing. It was evident in the first minute that 

 dart tags, streamer tags, and cinch-up tags would not 

 stay within the cucumber body wall and these methods 

 were not considered further. 



Next, 5) a rope gun was tested as a means of scarring 

 (branding) animals. Rope guns are normally used to 

 burn through rope by applying the hot tip to the surface 

 of a rope. For tagging purposes, the rope gun tip was ap- 

 plied to the dermis of C. frondosas to produce a recogniz- 

 able scar; the process is similar to that used in branding 

 cattle. Although the rope gun created a noticeable mark, 

 many animals already possessed significant scarring 

 from being dragged during harvesting or from interac- 

 tions with fishing gear and other marine organisms, and 

 the new scar would not stand out to an observer. The 

 branding method was therefore also discarded. 



Finally, 6) liquid orange and yellow fluorescent dyes 

 composed of visible implant elastomer (VIE) were in- 



jected into the animals. VIE is a silicone-based mate- 

 rial that is mixed immediately before use and quickly 

 becomes a pliable, biocompatible solid. VIE tags were 

 injected internally beneath the epidermal tissue within 

 tube feet, along the body wall, or near the oral cavity. 

 The dye did not spread and all marks were small pin 

 points visible only under ultraviolet light. 



Short and long double T-bar tags and fluorescent dyes 

 served as the remaining tagging methods studied dur- 

 ing the course of the investigation. Seventy tagged sea 

 cucumbers from the Gulf of Maine were observed over 

 time (Table 1). Ten animals were injected with orange 

 and yellow fluorescent dyes and 45 animals were punc- 

 tured with long or short T-bar tags. Long tags had a 

 distance of 45 mm between T-bar ends. Short tags had 

 a distance of 19 mm between T-bar ends. Twenty-one 

 tags punctured the body wall just under the muscle so 

 that one end remained inside the animal (single-anchor 

 tags). The remaining 24 passed completely through the 

 body wall twice so that both ends of the T-bar tags were 

 exposed (double-pass tags). Finally, 15 control animals 

 were punctured with the tagging gun, 9 with double 

 punctures and 6 with single punctures. Sea cucumbers 

 were kept in tanks in the laboratories at the Maine 

 Department of Marine Resources in West Boothbay 

 Harbor, Maine. The presence and absence of tags was 

 noted every day from April to September 2003 for each 

 sample. Notation was made when tags were partially in 

 place or no longer observable at all. 



