YoNAH Encounter

The Years of the North Atlantic Humpback whale

Dataset credit

Peter Stevick, University of Southern Maine


Primary contact Peter Stevick Bioscience Research Institute, University of Southern Maine
Data entry Ei Fujioka Duke University



The Years of the North Atlantic Humpback whale (YoNAH) is the broadest-ranging, most intensive study ever undertaken of a marine mammal species. Standardized sampling protocols were used in all areas to minimizes biases due to sampling. The YoNAH project collected photographs of individually distinctive natural markings, genetic samples and behaviour data on humpback whales in the North Atlantic Ocean. Field work began in January 1992 with a large-scale study of humpbacks in their principal West Indies breeding range at Silver Bank, Navidad Bank and Samana Bay, Dominican Republic; and Mona Passage, Puerto Rico. During summer, sampling was conducted in all the known major North Atlantic feeding grounds: the Gulf of Maine, Gulf of St. Lawrence, Newfoundland, Labrador, southwestern Greenland, Iceland, and Norway. In 1993 the same schedule of field work was repeated.


The YoNAH project is a unique research program utilizing photo-identification techniques and molecular genetics to conduct an intensive survey of the population ecology of humpack whales throughout their known North Atlantic range. This internationally collaborative project involves scientists from seven nations. YoNAH's vast database supports a wide range of scientific investigations and also provides reliable, detailed information on which to base management policy. Archives of photographs, tissue samples and data will provide a valuable legacy for future research.

Supplemental information

[2015-03-24] A sighting record at 1993-02-07 10:45:00 had a wrong animal count of zero. The value is replaced with a blank representing species presence only. The notes for this sighting mentions "NO GROUP SIZE ESTIMATE".

A sighting record at 1992-08-04 15:00:00 had a wrong animal count of zero. The value is replaced with "1" that is an average of min and max counts, 0 and 2 respectively.

Data collection and analyses were conducted by reserach groups familiar with the study sites and with a history in use of these techniques for the study of humpback whale ecology. Allied Whale is responsible for photographic analysis and for database management. All the 5,500 photographs have been compared to one another to identify re-sightings. The accompanying databases are receiving final corrections and revisions. There are five datasets from YoNAH, including this one.
Behavior of whales were recorded in some surveys.
Biopsy samples and photographs were taken if possible.
Ships efforts and sightings of species other than humpback whales are recorded in the Effort dataset.
Those datasets can be linked with LINKKEY field.

For those records having null starttime but non-null endtime, endtime was added to date the date/time of the observation.


Nils Oien. 2003. Segregation of migration by feeding ground origin in North Atlantic humpback whales (Megaptera novaeangliae). Journal of Zoology, London. 259 (2003).



Attributes described below represent those in the original dataset provided by the provider.
Only minimum required attributes are visible and downloadable online. Other attributes may be obtained upon provider's permission.

Attributes in dataset

Attribute (table column)Description
linenodefinition not provided
recnodefinition not provided
dateDate of the sighting
vesselidVessel ID
cruiseCrouse No
encounterEncounter ID
linkkeyLink key
group_Group ID
minMinimum number of group size
maxMaximum number of group size
starttimeStart time
endtimeEnd time
latddLatitude in decimal degree
longddLongitude in decimal degree
locsourceLocation source
classdefinition not provided
mcdefinition not provided
certaintydefinition not provided
wasdefinition not provided
becomesdefinition not provided
notesdefinition not provided
surveyareadefinition not provided
excludeddefinition not provided
behavcountdefinition not provided
photocountNumber of photos taken
biopsycntNumber of biopsy taken
speciesSpecies name
tsnTaxonomic Serial Number by ITIS
geomdefinition not provided
oiddefinition not provided
tprecisionAccuracy of the date/time.
Marine mammals4,215
Sea turtles0
Rays and sharks0
Other species0
Non spatial0
Non species0
Date, Begin1992-01-15
Date, End1993-12-08
Temporal prec.111110
Latitude18.00 - 78.15
Longitude-70.63 - 40.60
Coord. prec.4 decimal digits
Data typeAnimal sighting
EffortYES (ID: 278)
Traveled (km)16,733
Effort hours1,071
Contr. through
Sharing policy CC-BY-NC (Minimum)
Shared with OBIS
GBIF (via DOI)
See metadata in static HTML
See metadata in FGDC XML
See download history / statistics