Harbor Porpoise Survey 1992 (AJ92-01)

NOAA Northeast Fisheries Science Center (NEFSC)

The ship survey was performed from 29 July 1992 to 06 September 1992,
starting and ending in Woods Hole, MA. The study area, covering approximately 13,300 nmi2, was from Portland, ME to St. John, New Brunswick over to Port Joli, Nova Scotia on the southeast side of Nova Scotia.

PRIMARY OBJECTIVE
Estimate the abundance of harbor porpoises in the Gulf of Maine - Bay of Fundy - Scotian shelf
area.

SECONDARY OBJECTIVES
1) Determine the spatial distribution patterns of harbor porpoises, and investigate if the patterns are correlated with hydrographic or biological features, such as, the depth, temperature or salinity of the water or with targets seen on an acoustic fish finder.
2) Estimate the abundance and spatial distribution of other cetaceans.
3) Determine if harbor porpoise avoid this ship, and if so, at what distance.
4) Use a 17 foot Zodiac rigid-hulled inflatable boat (RIB) and the R/V Abel-J to survey the Penobscot Bay - Blue Hill Bay area and other bays and harbors along the Maine and Nova Scotia coast.
5) Determine if there is a spatial distribution pattern of mother-calf pairs of harbor porpoise.
6) Compare the abundance estimate and spatial distribution of harbor porpoise as seen this year with that seen in previous years.
7) Determine dive time patterns of individual and groups of harbor porpoises around the sighting platform.
8) Investigate the utility of 2 new electronic data entry systems.
9) Determine the distribution of marine mammals between the northeastern edge of the study area and Halifax, Nova Scotia, on Brown' s Bank, and on the continental shelfbreak in the area south of Brown' s Bank.

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

This section explains attributes included in the original dataset. OBIS-SEAMAP restricts the attributes available to the public to date/time, lat/lon and species names/counts only. Should you need other attributes described here, you are encouraged to contact the data provider.

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
dataset	Dataset name
lineno	Line number
cruise	Cruise number designated by NEFSC
date	Date when the record was recorded
time	Time of the observation (local time)
latitude	Latitude in decimal degrees
longitude	Longitude in decimal degrees
species	Code of species sighted
common	Species common name.
tsn	ITIS Taxonomic Serial Number added by OBIS-SEAMAP
scientific	Species scientific name
group_	Group name the species belongs to
rank	Rank such as species, genus and family
herdsize	An estimate of the number of individuals.
transect	Transect no.
leg	Leg no.
excluded	For internal use
geom	Geometry field added by OBIS-SEAMAP
oid	Unique ID number (generated by OBIS-SEAMAP)