MTN 70:9-10 Recognition Of A Captured Head-Started Kemp's Ridley Turtle By Its Living Tag

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RECOGNITION OF A CAPTURED HEAD-STARTED KEMP'S RIDLEY TURTLE BY ITS LIVING TAG

On the night of August 3, 1994, a commercial fisherman caught a live Kemp's ridley sea turtle (Lepidochelys kempii) during shrimping operations with a skimmer net in Bayou Lafourche approximately three miles south of Golden Meadow, Louisiana (29°17'15" N, 90° 13'45" W). The skimmer net is used to catch white shrimp (Penaeus setiferus) in shallow waters (Hein and Meier 1994). The following morning (August 4, 1994), the fisherman transferred the turtle to the Louisiana Department of Wildlife and Fisheries' (LDWF) Lyle S. St. Amant Marine Laboratory at Grand Terre, Louisiana. The turtle was in good condition, measuring 39.4 cm straight carapace length and 38.7 cm straight carapace width. At that time, LDWF personnel detected a white spot on left costal scute 2 and a faint scar on the ventral surface of the right foreflipper. Thinking the white spot could be a "living tag" (Fontaine et al. 1989; Fontaine et al. 1988; and Caillouet et al. 1986) and the scar on the ventral side of the foreflipper an indication where a flipper tag had been attached, the junior author reported it to the National Marine Fisheries Service (NMFS) Laboratory in Galveston, Texas.

The Galveston Laboratory shipped a portable, battery powered, passive integrated transponder (PIT) tag reader to the St. Amant Laboratory. The reader detected PIT tag 7F7D343B7B, indicating that the ridley was from the 1991 year-class head-started in Galveston. When originally released on May 19, 1992, 23 nautical miles offshore of Galveston Island, the turtle measured 14.7 cm straight carapace length and 13.6 cm straight carapace width. The turtle was at large for 806 days before its capture in Bayou Lafourche and had grown 24.7 cm in length and 25.1 cm in width.

While at the St. Amant Laboratory, the turtle was held in a 6-foot diameter, flow-through seawater tank, was fed fresh fish and shrimp daily, and appeared to be normal. The turtle was released by LDWF into the Gulf of Mexico on September 6, seven nautical miles south of Grand Isle, Louisiana (29°11'12" N, 89°53'42" W).

This occurrence suggests that the living tag is not difficult to discern when Kemp's ridleys are examined carefully. Examination for living tag, PIT tag and magnetic wire tags, are essential since foreflipper tags are usually lost (Fontaine et al. 1993), in this case within 2.3 yr after release. Observations of this kind demonstrate the value of increased emphasis on tag detection throughout the range of the species and especially at the nesting beach at Rancho Nuevo, Mexico (Byles 1993; Williams 1993; Eckert et al. 1994). All Kemp's ridleys found stranded or captured in any area and under any situation, either alive or dead, should be examined closely for internal tags and signs of living tags (a grafted patch of pale plastron tissue on the carapace), and the results reported to the senior author.

Caillouet, C. W., Jr., C. T. Fontaine, S. A. Manzella, T. D. Williams and D. B. Revera. 1986. Scutes reserved for living tags. Marine Turtle Newsletter 36:5-6.

Byles, R. 1993. Head-start experiment no longer rearing Kemp's ridleys. Marine Turtle Newsletter 63:1-3.

Eckert, S. A., D. Crouse, L. B. Crowder, M. Maceina and A. Shah. 1994. Review of the Kemp's Ridley Sea Turtle Headstart Program, 22-23 September 1992, Galveston, Texas. NOAA Tech. Memo. NMFS-OPR-3. U. S. Dept. Commerce. 9 pp.

Fontaine, C. T., D. B. Revera, T. W. Williams and C. W. Caillouet, Jr. 1993. Detection, verification and decoding of tags and marks in head started Kemp's ridley sea turtles, Lepidochelys kempii. NOAA Tech. Memo. NMFS-SEFC-334. U. S. Dept. Commerce. iii + 40 pp.

Fontaine, C. T., S. A. Manzella, T. D. Williams, R. M. Harris and W. J. Browning. 1989. Distribution, growth and survival of head started, tagged and released Kemp's ridley sea turtles (Lepidochelys kempi) from year-classes 1978-1983, p.124-144. In: C. W. Caillouet, Jr. and A. M. Landry, Jr. (Editors), Proc. First International Symposium on Kemp's Ridley Sea Turtle Biology, Conservation and Management. Texas A&M University, Sea Grant College Program TAMU-SG-89-105. vi + 260 pp.

Hein, S. and M. Paul. 1994. Skimmers: their development and use in coastal Louisiana. Louisiana Dept. Wildl. Fish., Office of Fisheries, Marine Fisheries Division. Bourg, Louisiana. 21 pp.

Williams, P. 1993. NMFS to concentrate on measuring survivorship, fecundity of head-started Kemp's ridleys in the wild. Marine Turtle Newsletter 63:3-4.

CLARK T. FONTAINE, National Marine Fisheries Service, Southeast Fisheries Science Center, Galveston Laboratory, 4700 Avenue U, Galveston, Texas 77551 and MARK A. SCHEXNAYDER, Louisiana Department of Wildlife and Fisheries, P. O. Box 37, Grand Isle, Louisiana 70358 USA.