Abundance of Rocky Reef Fishes, Invertebrates and Algae, Reef Check California (RCCA), 2006 - 2017

Registros de Dados

Os dados deste recurso de evento de amostragem 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 19.375 registros.

Também existem 2 tabelas de dados de extensão. Um registro de extensão fornece informações adicionais sobre um registro do núcleo. O número de registros em cada tabela de dados de extensão é ilustrado abaixo.

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.

Direitos

Pesquisadores devem respeitar a seguinte declaração de direitos:

O editor e o detentor dos direitos deste trabalho é United States Geological Survey. To the extent possible under law, the publisher has waived all rights to these data and has dedicated them to the Public Domain (CC0 1.0). Users may copy, modify, distribute and use the work, including for commercial purposes, without restriction.

GBIF Registration

Este recurso foi registrado no GBIF e atribuído ao seguinte GBIF UUID: 4ef2bed0-d40f-49c9-bb64-c46a301a5a72.  United States Geological Survey publica este recurso, e está registrado no GBIF como um publicador de dados aprovado por GBIF-US.

Palavras-chave

Samplingevent

Contatos

Cobertura Geográfica

The coast of southern Oregon and California.

Métodos de Amostragem

A survey, at minimum, consists of 18 band transects: 6 core transects and 12 fish-only transects. During each transect, an area of 30 m x 2 m is surveyed (60 m2) in approximately 10-15 minutes. Half of the transects (3 core and 6 fish-only) are conducted inshore in shallower waters, while the other half are conducted offshore in deeper waters. Transects must be haphazardly placed in rocky reef habitat, spaced at least 5 m apart, and follow a depth contour as much as possible. No transects are conducted at depths greater than 18 m. During each core transect, divers search for invertebrates, kelp, and fish. They also perform a Uniform Point Contact (UPC) survey to characterize the substrate, its topography, and any organisms directly covering it. Divers are required to use a flashlight, and are instructed to search the transect area as thoroughly as possible while remaining approximately within the 10-15 minute survey interval. Fish are surveyed first, while laying the transect tape, so that their behavior is minimally affected by the divers' presence. Before beginning, divers assess visibility: One diver holds up a hand, and the other diver swims away until they can no longer distinguish the fingers. This distance defines the visibility measurement; a visibility of at least 3 m is required to perform fish surveys. If the visibility is sufficient, divers search for fish within the 30 m x 2 m transect area, up to a height of 2 m off the bottom, for a total survey volume of 120 m3. They identify and size all fish observed that are part of the RCCA's list of 35 key fish taxa. Size is estimated by eye to the nearest centimeter. If a large number of fish of the same species is observed, divers may estimate the minimum and maximum size of the group. Young of the year rockfish (Genus Sebastes) are always given a minimum size of 1 cm and a maximum size of 10 cm. Divers also record the presence or absence of all invertebrates and algae from the RCCA's list of key taxa during core transects. Invertebrates must be at least 2.5 cm in size to be recorded, except for anemones (Order Actinaria) and gorgonians (Genuses Muricea and Leptogorgia). Anemones must be at least 10 cm tall or wide while gorgonians must be at least 10 cm tall. If divers encounter a large density of a particular invertebrate taxa, that taxa may be subsampled. To subsample, divers count 50 individuals, and then note where they are along the transect line (e.g., 50 urchins were observed in 17 m). Red abalone (Haliotis rufescens) are not subsampled. Densities for subsampled taxa have already been adjusted to have units of number of individuals per 60 m2 in this data submission. When giant kelp (Macrocystis pyrifera) are observed, the number of stipes for each individual is recorded. Finally, as part of the UPC survey, divers examine the substrate at each of 30 points at 1 m intervals along the transect tape and characterize it as one of 5 categories: sand, cobble, boulder, bedrock and other. At each point, the topography, or relief, of the substrate is also characterized as one of 4 categories: 0-10 cm, 10 cm - 1 m, > 1 m - 2 m, and > 2 m. Finally, divers record which organisms (if any) are covering the substrate at each point. In addition to the 6 core transects, divers also perform 12 fish-only transects (6 inshore and 6 offshore). Occasionally, more than 12 fish-only transects are performed. All fish-only transects use the same protocols for fish surveys described above. For additional details on survey methods, see the RCCA monitoring protocol, available here: https://opc.dataone.org/view/doi%3A10.25494%2FP69885

Descrição dos passos do método:

1. Data were retrieved from where they are archived on the Ocean Protection Council's DataONE node and saved in Comma Separated Values (.csv) files.
2. Data were transformed from the native format output into a table structure using Darwin Core Archive (DwC-A, occurrence core, measurement or fact extension) term names as column names. Python 3 processing scripts were used to run the data format conversion.

Metadados Adicionais