Demersais survey in the Azores between 1996 and 2013

OBIS and EurOBIS

Demersal surveys performed with bottom longline during research cruises around Azorean islands and several seamounts. Surveys conducted annually (few exceptions) from 1996 to 2013.
Sampling is performed using a "stone-buoy longline" similar to the one used in the commercial demersal fishery in the Azores. The sampling is stratified and random based on depth and geographic areas from 25 meters to 1200 meters mostly, but few sets down to 2000 meters. In some sets a different longline design was used (see Menezes et al. 2009). Soak time was usually 2 to 3 hours, but deeper sets (below 1000 meters) have longer soaks times. Chopped and salted sardines were used as bait.

N/A

This dataset was downloaded from OBIS (https://obis.org/). The records for only marine mammals, seabirds, sea turtles and rays and sharks were extracted. Records with no longitude/latitude or no date (eventDate) were excluded.
OBIS dataset page:
https://obis.org/dataset/873ef09c-82b6-4d92-bc91-252c11f5e97d
Data Provider's dataset page:
http://ipt.vliz.be/eurobis/resource?r=demersais_survey_azores_1996_2013

The dataset has been updated over time as outlined below. Each entry includes the version number, release date, type of change, and a short description.

Overview

Attributes are defined by OBIS.

Attributes described below represent those in the original dataset provided by the provider.
All attributes are included in the downloadable file (CSV or ESRI File Geodatabase) for "Complete Set of Dataset".

Attributes in dataset

Attribute (table column)	Description
oid	Internal ID
id	Record ID
dataset_id	Dataset ID
scientificname	Scientific name
vernacularname	Vernacular name
aphiaid	Aphia ID
taxonrank	taxononic rank
individualcount	Group size / individual count
eventdate	Event date (precision varies)
eventtime	Event time
decimallatitude	Latitude in decimal degrees
decimallongitude	Longitude in decimal degrees
coordinateprecision	Coordinate precision
catalognumber	Catalog number
collectioncode	Collection code
occurrencestatus	Occurrence status
basisofrecord	Basis of record (HumanObservation / MachineObservation)
modified	Date/time the record was modified
node_id	Node ID
occurrenceid	Occurrence ID
occurrenceremarks	Occurrence remarks
eventid	Event ID
institutioncode	Institution code
lifestage	Life stage
sex	Sex of the animal if known
species	Species by provider
datasetid	Dataset ID by provider
country	Country
locality	Location of ocean
waterbody	Details of ocean
dropped	Flag indicating the record was dropped (always false)
absence	Flag indicating the record represents the absence of the species (always false)
marine	Flag indicating the record is for marine life (always true)
obs_datetime
tprecision
on_land
date_in_future