NEFSC 1995 AJ9501 (Part I)

National Marine Fisheries Service

The ship survey was performed from 22 July 1991 to 30 August 1991 to estimate the abundance and spatial distribution of harbor porpoises. The study area, covering approximately 13,300 nm, was from Port Clyde, Maine to St. John, New Brunswick over to the Nova Scotian coast, up to Liverpool, Nova Scotia.

The primary objectives were:

1) Estimate the abundance of harbor porpoises in the Gulf of Maine - Bay of Fundy - Nova Scotia area; and

2) Investigate if there are any spatial distribution patterns of the harbor porpoises, and if those patterns are correlated with water depth or harbor porpoise group size.

The secondary objectives were:

1) Estimate the abundance and spatial distribution of other cetaceans;

2) Determine if harbor porpoise avoid this ship, and if so, at what distance;

3) Determine if there is a spatial distribution pattern of mother-calf pairs of harbor porpoise;

4) Compare the abundance estimate and spatial distribution of harbor porpoise as seen this year with that seen in previous years;

5) Investigate if inland bays can be surveyed using a rigidhull inflatable boat as the observation platform in a line transect survey; and

6) Determine if Buckland's sighting procedure (1991), which is a line transect survey using both a primary and marking team, is a feasible procedure to estimate the abundance of harbor porpoise in the Bay of Fundy area.

In addition to the sighting data, effort data was recorded every half hour or whenever conditions change. This dataset, therefore, should be used with the effort data.

Overview

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
cruise	Cruise number designated by NEFSC
year	definition not provided
month	definition not provided
day	definition not provided
time	Time when the record was recorded
lat	Latitude in decimal degrees
long	longitude in decimal degrees
species	Code of species sighted
size	Herd size
transect	Transect no.
leg	Leg no.
col_11	definition not provided
geom	definition not provided
oid	definition not provided