說明
Original provider: National Marine Mammal Laboratory Dataset credits: National Marine Mammal Laboratory Abstract: From 4 to 13 August 1991, as part of a larger study, Alaska harbor porpoise (Phocoena phocoena) abundance was investigated during an aerial survey throughout the coastal waters of Bristol Bay. A Twin Otter was used as the survey platform. The surveys were flown at an altitude of 152.2 m (500 ft) and at an airspeed of 185 km/h. A single zigzag trackline was flown along the north side of Bristol Bay, and the first of three identical sawtooth tracklines was flown along the south side. Line-transect methodology was used, and only those observations made during optimal conditions were analyzed. Density of harbor porpoises was calculated using line transect estimates based on perpendicular distances of sightings to the cruise track of the airplane. On average, porpoise group size and density for Bristol Bay was 1.17 (SE = 0.35) and 4.48 groups/100 km2 (SE = 1.38). Purpose: Although harbor porpoises, Phocoena phocoena, are known to occur throughout Alaska waters, few estimates of abundance exist. In 1991, the National Marine Mammal Laboratory initiated a 3 year study on Alaska harbor porpoises. The objectives of this program were to: 1) Obtain minimum population estimates in coastal waters using line transect methodology with a coefficient of variation for density estimates of less than 30% for each survey area, and 2) Establish a baseline for detecting changes in abundance through time, for analysis of trends. During the present study, it was not fiscally possible to survey all areas of the state in any one year. Accordingly, we selected sections of the state to survey in consecutive years to maximize the likelihood of including all of the animals for a particular area surveyed while minimizing the likelihood of significant movement between areas among survey years. Supplemental information: This dataset and associated effort data were updated on Sept 8, 2005. Those who downloaded them before that date should renew them.
資料紀錄
此資源出現紀錄的資料已發佈為達爾文核心集檔案(DwC-A),其以一或多組資料表構成分享生物多樣性資料的標準格式。 核心資料表包含 38 筆紀錄。
此 IPT 存放資料以提供資料儲存庫服務。資料與資源的詮釋資料可由「下載」單元下載。「版本」表格列出此資源的其它公開版本,以便利追蹤其隨時間的變更。
版本
以下的表格只顯示可公開存取資源的已發布版本。
如何引用
研究者應依照以下指示引用此資源。:
Dahlheim, M., A. York, R. Towell, J. Waite, and J. Breiwick. 2000. Harbor porpoise (Phocoena phocoena) abundance in Alaska: Bristol Bay to southeast Alaska, 1991-1993. Marine Mammal Science. 16(1): 28-45.
權利
研究者應尊重以下權利聲明。:
此資料的發布者及權利單位為 OBIS-SEAMAP。 This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC 4.0) License.
GBIF 註冊
此資源已向GBIF註冊,並指定以下之GBIF UUID: b3be552e-b48c-4f62-8ace-d53f5f85d65d。 OBIS-SEAMAP 發佈此資源,並經由Ocean Biodiversity Information System同意向GBIF註冊成為資料發佈者。
關鍵字
Occurrence,Aircraft,Sightings,harbor porpoise,Phocoena phocoena,abundance,aerial survey,marine mammal survey,survey,marine mammal,cetacean; Observation; Occurrence
外部資料
此資源尚有其他格式可用
OBIS-SEAMAP Dataset Page | http://seamap.env.duke.edu/dataset/128 UTF-8 Interactive map |
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FGDC Metadata | http://seamap.env.duke.edu/dataset/128/xml UTF-8 XML |
聯絡資訊
- 元數據提供者 ●
- 散布者
地理涵蓋範圍
Alaska,Bristol Bay
界定座標範圍 | 緯度南界 經度西界 [55.465, -163.298], 緯度北界 經度東界 [58.979, -158] |
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分類群涵蓋範圍
Scientific names are based on the Integrated Taxonomic Information System (ITIS).
Order | Cetacea (cetaceans) |
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Species | Delphinapterus leucas (Beluga), Eschrichtius robustus (Gray Whale), Phocoena phocoena (Harbor Porpoise), Orcinus orca (Killer Whale), Balaenoptera acutorostrata (Minke Whale), Lagenorhynchus obliquidens (Pacific White-sided Dolphin) |
時間涵蓋範圍
起始日期 / 結束日期 | 1991-08-04 / 1991-08-13 |
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計畫資料
無相關描述
計畫名稱 | NMML Harbor Porpoise Aerial Survey, Bristol Bay, Replicate 1, 1991 |
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經費來源 | NA |
參與計畫的人員:
- 擁有者
- 擁有者
取樣方法
NA
研究範圍 | NA |
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方法步驟描述:
- NA
收藏資料
蒐藏名稱 | zd_128 |
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蒐藏編號 | zd_128 |
上層採集品識別碼 | OBIS-SEAMAP |
額外的詮釋資料
marine, harvested by iOBIS
目的 | Although harbor porpoises, Phocoena phocoena, are known to occur throughout Alaska waters, few estimates of abundance exist. In 1991, the National Marine Mammal Laboratory initiated a 3 year study on Alaska harbor porpoises. The objectives of this program were to: 1) Obtain minimum population estimates in coastal waters using line transect methodology with a coefficient of variation for density estimates of less than 30% for each survey area, and 2) Establish a baseline for detecting changes in abundance through time, for analysis of trends. During the present study, it was not fiscally possible to survey all areas of the state in any one year. Accordingly, we selected sections of the state to survey in consecutive years to maximize the likelihood of including all of the animals for a particular area surveyed while minimizing the likelihood of significant movement between areas among survey years. |
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替代的識別碼 | http://ipt.env.duke.edu/resource?r=zd_128 |