Movement patterns of Kemp’s ridley sea turtles in the northwestern Gulf of Mexico 2004-2007

Original provider:
Erin Seney and Andre Landry, Texas A&M

Dataset credits:
Erin Seney and Andre Landry, Sea Turtle & Fisheries Ecology Research Laboratory, Department of Marine Biology, Texas A&M University at Galveston

Abstract:
The Kemp's ridley sea turtle <i>Lepidochelys kempii</i> is recovering from declines that reduced nesting from a single-day estimate of 10000 to 40000 females in 1947 to <300 during the entire 1985 nesting season. Although beach monitoring is crucial to estimating nesting population size and activity, in-water data are essential for understanding population dynamics, evaluating management strategies, and ensuring the species’ continued recovery. Fifteen immature and 7 adult female ridleys were fitted with platform terminal transmitters and released off the upper Texas coast during 2004 through 2007. Immature individuals were tracked primarily during warmer months and exhibited preferences for tidal passes, bays, coastal lakes, and nearshore waters, although movement patterns varied among years. Females tracked during their inter-­nesting intervals remained in the vicinity of the upper Texas coast and, upon entering the post-nesting stage, moved eastward along the 20 m isobath to foraging areas offshore of central Louisiana. Satellite telemetry indicated that inshore and continental shelf waters of the northwestern Gulf of Mexico serve as developmental, migratory, inter-nesting, and post-nesting habitat for the Kemp’s ridley. Projected population growth will likely lead to increased use of the northwestern Gulf by the species and more frequent encounters with human activities. The extent of such anthropogenic interactions and need for mitigation measures should be examined and considered by natural resource managers to facilitate continued recovery of this and other sea turtle species in the Gulf of Mexico. Likewise, research efforts should be continued to better understand seasonal in-water distributions, abundances, population dynamics, and mortality risks to all life history stages.

原始提供方：艾琳·西尼（Erin Seney）与安德烈·兰德里（Andre Landry），德克萨斯农工大学（Texas A&M）

数据集致谢：艾琳·西尼、安德烈·兰德里，德克萨斯农工大学加尔维斯顿分校海洋生物学系海龟与渔业生态研究实验室

摘要：肯普氏丽龟（Kemp's ridley sea turtle, *Lepidochelys kempii*）正从种群锐减中恢复：1947年其单日筑巢雌性个体数量曾达10000至40000只，而1985年整个筑巢季的筑巢雌性数量已不足300只。尽管海滩监测对估算筑巢种群规模与活动情况至关重要，但水下数据对于理解种群动态、评估管理策略以及保障该物种持续恢复而言不可或缺。2004年至2007年间，研究人员为15只亚成体肯普氏丽龟与7只成年雌性肯普氏丽龟安装了平台终端发射器（platform terminal transmitter），并在得克萨斯州北部近岸海域放归。亚成体个体主要在暖季被追踪，其活动偏好潮汐通道、海湾、沿海湖泊与近海水域，不过不同年份的移动模式存在差异。在筑巢间隔期被追踪的雌性个体始终停留在得克萨斯州北部近岸海域周边；当进入筑巢后阶段时，它们会沿20米等深线向东移动，前往路易斯安那州中部近海的觅食区域。卫星遥测（satellite telemetry）结果显示，墨西哥湾西北部的近岸与大陆架水域是肯普氏丽龟的发育、洄游、筑巢间隔以及筑巢后栖息生境。预计种群增长将可能导致该物种在墨西哥湾西北部的使用频次增加，与人类活动的相遇也会更为频繁。自然资源管理者应当审视并考量这类人为交互的范围以及采取缓解措施的必要性，以推动该物种与墨西哥湾其他海龟物种的持续恢复。同样，应当持续开展研究工作，以更全面地了解所有生活史阶段个体的季节性水下分布、种群丰度、种群动态以及死亡风险。