Cetacean Monitoring undertaken during the Mackerel Egg Survey (MEGS) June 2019

The Mackerel egg survey is undertaken every 3 years by the Fisheries Ecosystems Advisory Services (FEAS) department of the Marine Institute of Ireland as part of a series of international egg surveys co-ordinated by the International Council for the Exploration of the Seas (ICES). The MEGS provides a unique opportunity for surveillance of the summer distribution of cetaceans in both shelf water and deep water habitats along Ireland’s Atlantic margins which can be difficult to reach by other means.

The Department of Arts, Heritage and the Gaeltacht (DAHG), through the Marine Institute, commissioned a cetacean survey from the MRV Corystes during the Mackerel Egg Survey (MEGS), running from 9th to 29th of June 2019.

A standard, single platform line transect survey methodology was employed by the cetacean observer with additional visual point sampling at oceanographic sampling stations. Survey transects were undertaken at speeds of 5-10 knots, with fishing activity being conducted at speeds of 3-4 knots. The cetacean observer’s survey effort was maximized and optimized during periods of sea state less than or equal to sea state 6 and with visibility of greater than 1km. A total of 127 hours and 57 minutes of survey effort was conducted over the course of the MEGS 2019 survey. In total, 126 hours and 18 minutes of survey effort were conducted using a line transect methodology, while 1 hours and 38 minutes of effort were conducted using the point sampling methodology.

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Theme Environment
Date released 2022-06-17
Date updated 2023-11-20
Dataset conforms to these standards The INSPIRE Directive or INSPIRE lays down a general framework for a Spatial Data Infrastructure (SDI) for the purposes of European Community environmental policies and policies or activities which may have an impact on the environment.
Rights notes ['http://creativecommons.org/licenses/by/4.0/', 'Copyright Government of Ireland. This dataset was created by National Parks and Wildlife Service, Department of Housing, Local Government and Heritage. This copyright material is licensed for re-use under the Creative Commons Attribution 4.0 International licence. http://creativecommons.org/licenses/by/4.0/', 'otherRestrictions']
Update frequency Other
Language English
Geographic coverage in GeoJSON format {"type":"Polygon","coordinates":[[[-10.650444030762, 50.807923689449],[-10.650444030762, 55.993470564449], [-5.289115905762, 55.993470564449], [-5.289115905762, 50.807923689449], [-10.650444030762, 50.807923689449]]]}
Spatial Reference Systems (SRS) WGS 84 (EPSG:4326)
Vertical Extent {"verticalDomainName": "EPSG Projection 5731 - Malin Head height", "minVerticalExtent": "0", "maxVerticalExtent": "1014"}
Provenance information Survey transect were undertaken at speeds of 5-10 knots, with horizontal plankton tows conducted at speeds of 3-4 knots. The cetacean observer’s survey effort was maximized and optimized during periods of sea state less than or equal to sea state 6 and with visibility of greater than 1km. Additional visual point sampling at oceanographic sampling stations and incidental recording was also employed; however line transect survey effort was prioritised by the observers. The Cybertracker (https://cybertracker.org) data collection software was configured for optimum use on the survey. Cybertracker was used to record all positional, environmental and sightings data. Using a portable GPS receiver with USB connection, the Cybertracker software automatically recorded the ships position directly into a Microsoft Access database every 5 seconds. Environmental data was recorded in Cybertracker every 15-30 minutes, and included data such as; wind speed, wind direction, sea state, swell, visibility, cloud cover and precipitation. The data was time stamped by Cybertracker and saved in the Access database. If environmental conditions changed at any point, the cetacean observer recorded an environmental update of the above listed data. Survey effort start- and end- points, together with any waypoints or other ancillary information (such as line changes, changes in survey activity, other vessel activity, etc.) were also recorded on Cybertracker. The GPS position of each cetacean sighting was time stamped and digitally marked using Cybertracker. The distance of each sighting from the ship was estimated using a fixed interval range finder (Heinemann, 1981), while the bearing from the ship (where the ship’s heading = 0°) was estimated with the aid of an appropriately positioned angle board. This data, along with data such as species identification, group size, composition, heading, sighting cues, surfacing interval, behaviour and any associations with birds or other cetaceans (Ó Cadhla et al. 2004), was also recorded on the time stamped Cybertracker sighting record page. Where species identification could not be confirmed, sightings were recorded at an appropriate taxonomic/ confidence level (i.e. probable, possible, unidentified whale, unidentified dolphin etc.). Some data was amended to comply with GDPR legislation and open data publication guidelines.
Period of time covered (begin) 2019-06-09
Period of time covered (end) 2019-06-29