Tampa Bay 2023-2024 Manatee Distribution Survey Observations

Aerial distribution surveys are used by marine mammal biologists from Florida Fish & Wildlife Conservation Commission-Fish & Wildlife Research Institute (FWC-FWRI) and other agencies to determine the seasonal distribution of manatees. Most surveys are conducted from small, four-seat, high-winged airplanes (Cessna 172 or 182) flying at a height of 500-1000 ft at a speed of 70-90 kts. This survey was conducted by one aircraft mostly following historical flight paths used for past county-wide distribution surveys. However, some changes were made to shorten the flight route or to cover areas not flown in previous paths. See trackline metadata for details of flight path modifications. Flight paths generally curved parallel to the shoreline, and the airplane circled when manatees were spotted until a count of the number of animals in each group was obtained. Circling was limited to 3 passes unless a group was unusually large and aerial photos were used in some cases to confirm counts. Sightings data were recorded on paper maps and entered into a GIS shapefile for spatial analysis using NAIP 2021 - 2022 imagery and recorded flight paths as a reference. GIS is a computer software system for representing data spatially and for conducting spatial analyses. Counts presented in this dataset have not been corrected for detection bias (either perception or availability) and the absence of sightings in an area does not mean that no animals were present. This dataset includes recorded manatee sightings from 24 surveys flown on the following dates: 13 September 2023; 6 and 23 October 2023; 18 and 29 November 2023; 5 and 29 December 2023; 18 and 26 January 2024; 16 and 27 February 2024; 7 and 25 March 2024; 9 and 17 April 2024; 3 and 30 May 2024; 4 and 26 June 2024; 23 and 27 July 2024; 12 and 27 August 2024; 12 September 2024. FWC or Mote Marine Laboratory staff members were primary observers for these flights, and dual observers (two observers, one in the front seat and one in the rear seat) were present on some or all survey flights. The survey area includes the coastal areas of Tampa Bay, Florida from the Hillsborough-Manatee County line to Coffee Pot Bayou in southern Pinellas County. Some areas along the planned flight path may have been partially surveyed or not surveyed at all due to air traffic, weather, or other constraints present during individual surveys.佛罗里达鱼类与野生动物保护委员会-鱼类与野生动物研究所（FWC-FWRI）及其他机构的海洋哺乳动物生物学家，借助航空调查以探明海牛的季节性分布格局。绝大多数航空调查由四座小型上单翼飞机（赛斯纳172或赛斯纳182）执行，飞行高度设定为500至1000英尺，巡航速度为70至90节。本次调查采用单架作业飞机，主要沿用过往全县范围海牛分布普查的历史飞行航线，但为缩短航程或覆盖以往航线未涉及的区域，对航线作出了部分调整，具体修改细节请参阅航线元数据。 飞行航线通常呈弧形平行于海岸线延伸，当观测到海牛时，飞机将盘旋直至完成对每个海牛群体的个体数量统计。除非海牛群体规模异常庞大，否则盘旋次数限制为3次，部分场景下还会通过航拍照片辅助确认统计结果。 观测数据最初记录于纸质地图，之后被录入地理信息系统（Geographic Information System，GIS）形状文件（shapefile），以2021-2022年美国农业影像计划（National Agriculture Imagery Program，NAIP）影像及记录的飞行航线作为参考开展空间分析。地理信息系统是一类用于空间化呈现数据并开展空间分析的计算机软件系统。 本数据集所呈现的海牛数量统计未针对检测偏差（涵盖感知偏差与可获得性偏差）进行校正，且某一区域未观测到海牛，并不代表该区域不存在海牛个体。 本数据集涵盖了24次飞行普查的海牛观测记录，具体飞行日期如下：2023年9月13日；2023年10月6日、23日；2023年11月18日、29日；2023年12月5日、29日；2024年1月18日、26日；2024年2月16日、27日；2024年3月7日、25日；2024年4月9日、17日；2024年5月3日、30日；2024年6月4日、26日；2024年7月23日、27日；2024年8月12日、27日；2024年9月12日。 本次飞行普查的观测人员主要为佛罗里达鱼类与野生动物保护委员会（FWC）或莫特海洋实验室的工作人员，部分或全部普查航班采用双观测员配置，即前排与后排座椅各配备一名观测员。 本次普查区域覆盖佛罗里达州坦帕湾沿岸海域，范围从希尔斯伯勒-马诺特县界至皮尼拉斯县南部的咖啡壶湾。由于单次普查期间遭遇空中交通管制、恶劣天气或其他限制因素，规划航线中的部分区域可能仅完成了部分普查，或完全未开展普查。