Ontogenetic shifts in diet and habitat by juvenile green sea turtles (Chelonia mydas) along the middle and lower Texas coast.

Bibliographic Details
Main Author: Howell, Lyndsey
Other Authors: Landry, Andre M. (Thesis advisor)
Format: Thesis eBook
Language:English
Published: [College Station, Tex.] : [Texas A&M University], [2012]
Subjects:
Online Access:Link to OAK Trust copy

MARC

Tag First Indicator Second Indicator Subfields
LEADER 00000cam a2200000Ka 4500
001 in00002785790
005 20150922150922.0
006 m fo d
007 cr unu||||||||
008 121127s2012 txu obm 000 0 eng d
035 |a (OCoLC)ocn819413333 
035 |a (OCoLC)819413333 
035 |a (TxCM)http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11797 
040 |a TXA  |c TXA  |d UtOrBLW 
049 |a TXAM 
099 |a 2012  |a Thesis  |a 1969.1/ETD-TAMU-2012-08-11797 
100 1 |a Howell, Lyndsey. 
245 1 0 |a Ontogenetic shifts in diet and habitat by juvenile green sea turtles (Chelonia mydas) along the middle and lower Texas coast. 
264 1 |a [College Station, Tex.] :  |b [Texas A&M University],  |c [2012] 
300 |a 1 online resource. 
336 |a text  |b txt  |2 rdacontent 
337 |a computer  |b c  |2 rdamedia 
338 |a online resource  |b cr  |2 rdacarrier 
500 |a "Major Subject: Wildlife and Fisheries Sciences" 
588 |a Description from author supplied metadata (automated record created 2012-10-22 13:24:58). 
502 |b Master of Science  |c Texas A&M University  |d 2012  |o http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11797 
504 |a Includes bibliographical references. 
516 |a Text (Thesis) 
520 3 |a Effective population management of green sea turtles (Chelonia mydas) necessitates understanding the temporal variation in foraging grounds used in ontogenetic stages, and the effect that the assimilated diet within those habitats has on nutritional gain, growth and eventual reproductive output. Texas coastal waters provide foraging grounds critical to meeting the nutritional needs of green turtles during early life history. To characterize temporal shifts in foraging strategy stomach contents combined with stable carbon (Δ13C) and nitrogen (Δ15N) isotopes of scute tissue were examined across size classes of stranded juvenile green turtles from the middle and lower Texas coast during 2007-2010. Findings from dietary analysis generally corroborated those from stable isotopes in scute samples. Results indicate green sea turtles exhibit multiple shifts in diet and habitat along the Texas coast. Although isotope values in the tissues of some <25 cm SCL turtles signified recent recruitment to jetty habitat, most in this size class exhibited depleted Δ13C and enriched Δ15N values indicative of oceanic life. Reinforcing oceanic occupancy from stable isotope results was forage material dominated by oceanic items such as Sargassum spp., Scyphozoa spp., and plastic debris. Diet analysis of 25-34.9 cm SCL turtles implied regional differences existed in macroalgae and seagrass consumption. Enriched Δ13C and Δ15N values in newest scute suggest most turtles inhabited the jetty environment, where macroalgae is the most available forage. A definitive shift by >35 cm SCL turtles to inshore seagrass habitat was revealed by a diet of seagrasses and tissue enriched in Δ13C and depleted in Δ15N. This is the first study to integrate stomach contents of several green turtle size classes with tissue analysis of stable isotopes. The combination of these techniques provided an assessment of the effectiveness of stable isotope analyses in documenting diet and habitat shifts. Stomach content examination determined the most recent diet consumed within the habitat occupied, whereas stable isotope analysis provided a time-integrated synopsis of diet and habitat shifts. Findings indicate integration of stomach content and stable isotope analysis is highly effective for characterizing habitat use and foraging strategy of ontogenetic-stage green sea turtles. 
500 |a Electronic resource. 
650 4 |a Major Wildlife and Fisheries Sciences. 
653 |a Stable Isotope Analysis 
653 |a Stomach Content Analysis 
653 |a Ontogenetic Shifts 
653 |a Foraging Ecology 
653 |a Sea Turtles 
700 1 |a Landry, Andre M.,  |e thesis advisor. 
856 4 0 |u http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11797  |z Link to OAK Trust copy  |t 0 
948 |a cataloged  |b h  |c 2012/11/27  |d o  |e jstorlie  |f 11:17:33 am 
994 |a C0  |b TXA 
999 |a MARS 
999 f f |s f47d86da-4f67-317f-8590-c175c08fa577  |i a2b575a2-0215-34bd-8c22-36530bdda033  |t 0 
952 f f |a Texas A&M University  |b College Station  |c Electronic Resources  |d Available Online  |t 0  |e 2012 Thesis 1969.1/ETD-TAMU-2012-08-11797  |h Other scheme 
998 f f |a 2012 Thesis 1969.1/ETD-TAMU-2012-08-11797  |t 0  |l Available Online