Descrição
Original provider: National Marine Mammal Laboratory Dataset credits: National Marine Mammal Laboratory Abstract: On 6 July to 9 August 1992, as part of a larger study, Alaska harbor porpoise (Phocoena phocoena) abundance was investigated during an aerial survey off the south side of the Alaska Peninsula. Employing a Twin Otter as the survey platform, the second of two identical sawtooth tracklines was flown at an altitude of 152.2 m (500 ft) and at an airspeed of 185 km/h. 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 off the south side of the Alaska Peninsula was 1.1 (SE = 0.10) and 2.03 groups/100 km2 (SE = 1.65). 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 September 8, 2005. Those who downloaded them before that date should renew them.
Registros de Dados
Os dados deste recurso de ocorrência foram publicados como um Darwin Core Archive (DwC-A), que é o formato padronizado para compartilhamento de dados de biodiversidade como um conjunto de uma ou mais tabelas de dados. A tabela de dados do núcleo contém 41 registros.
This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.
Versões
A tabela abaixo mostra apenas versões de recursos que são publicamente acessíveis.
Como citar
Pesquisadores deveriam citar esta obra da seguinte maneira:
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.
Direitos
Pesquisadores devem respeitar a seguinte declaração de direitos:
O editor e o detentor dos direitos deste trabalho é OBIS-SEAMAP. This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC 4.0) License.
GBIF Registration
Este recurso foi registrado no GBIF e atribuído ao seguinte GBIF UUID: c15c7913-e0f4-44d6-a246-678ce908a9e5. OBIS-SEAMAP publica este recurso, e está registrado no GBIF como um publicador de dados aprovado por Ocean Biodiversity Information System.
Palavras-chave
Occurrence,Aircraft,Sightings,harbor porpoise,Phocoena phocoena,abundance,aerial survey,marine mammal survey,survey,marine mammal,cetacean; Observation; Occurrence
Dados externos
Os dados de recurso também estão disponíveis em outros formatos
OBIS-SEAMAP Dataset Page | http://seamap.env.duke.edu/dataset/136 UTF-8 Interactive map |
---|---|
FGDC Metadata | http://seamap.env.duke.edu/dataset/136/xml UTF-8 XML |
Contatos
- Proprietário ●
- Originador ●
- Ponto De Contato
- Provedor Dos Metadados ●
- Distribuidor
Cobertura Geográfica
Alaska Peninsula,Alaska
Coordenadas delimitadoras | Sul Oeste [55,314, -159,936], Norte Leste [57,638, -154,732] |
---|
Cobertura Taxonômica
Scientific names are based on the Integrated Taxonomic Information System (ITIS).
Ordem | Cetacea (cetaceans), Cetacea (cetaceans) |
---|---|
Espécie | Phocoenoides dalli (Dall's Porpoise), Balaenoptera physalus (Fin Whale), Phocoena phocoena (Harbor Porpoise) |
Cobertura Temporal
Data Inicial | 1992-07-31 |
---|
Dados Sobre o Projeto
Nenhuma descrição disponível
Título | NMML Harbor Porpoise Aerial Survey, Alaska Peninsula, Replicate 2, 1992 |
---|---|
Financiamento | NA |
O pessoal envolvido no projeto:
- Proprietário
- Proprietário
Métodos de Amostragem
NA
Área de Estudo | NA |
---|
Descrição dos passos do método:
- NA
Dados de Coleção
Nome da Coleção | zd_136 |
---|---|
Identificador da Coleção | zd_136 |
Identificador da Coleção Parental | OBIS-SEAMAP |
Metadados Adicionais
marine, harvested by iOBIS
Propósito | 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. |
---|---|
Identificadores alternativos | http://ipt.env.duke.edu/resource?r=zd_136 |