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Updated abundance estimates for cetacean Management Units in UK waters (Revised March 2022) 2022

Marine JNCC Publications UK Biodiversity 0963-8091 Cetacean JNCC report series Mammals Marine Species UK Species 680


In 2015, the Inter-Agency Marine Mammal Working Group (IAMMWG) defined Management Units (MUs) for the seven most common cetacean species found in UK waters (see JNCC Report 547; IAMMWG 2015): harbour porpoise (Phocoena phocoena), bottlenose dolphin (Tursiops truncatus), short-beaked common dolphin (Delphinus delphis), white-beaked dolphin (Lagenorhynchus albirostris), Atlantic white-sided dolphin (Lagenorhynchus acutus), Risso’s dolphin (Grampus griseus), and minke whale (Balaenoptera acutorostrata). Abundance estimates were calculated for each species within their respective MUs using the most recent data available at the time, notably estimates from the Small Cetacean Abundance in the European Atlantic and North Sea project (SCANS-II; Hammond et al. 2013).

This report details updated abundance estimates for these species and their MUs using the most up-to-date data available as of February 2021, notably SCANS-III (Hammond et al. 2017) and the ObSERVE Programme (Rogan et al. 2018). The cetacean MUs defined in this report are geographical areas in which animals of a particular species are found and management of human activities is applied. These updated estimates supersede those in the previous report (2015) and should be used in preference. MUs are used to inform statutory nature conservation body (SNCB) advice in several ways, including the assessment of environmental impacts in marine casework (e.g. through HRA, EIA).

This report, first published in May 2021, was republished in March 2022, in response to a minor revision: the citation dates under 'Source' in Tables 1 and 2 have been amended.

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Please note that updated management units were produced in March 2023 (see JNCC Report 734: Review of Management Unit boundaries for cetaceans in UK waters (2023)). Information provided in JNCC Report 734 supersedes the information in JNCC reports 547 and 680 (IAMMWG 2015, 2022), although the principles underlying the delineation of MUs and calculation of abundance estimates remain unchanged.

Resource type Publication

Topic category Environment

Reference date 2022·03·01

IAMMWG. 2022. Updated abundance estimates for cetacean Management Units in UK waters (Revised 2022). JNCC Report No. 680, JNCC Peterborough, ISSN 0963-8091.

This report details updated abundance estimates for the seven most common cetacean species found in UK waters and their Management Units (MUs), using the most up-to-date available.

Responsible organisation
Communications, JNCC publisher

Limitations on public access No limitations

Use constraints Available under the Open Government Licence 3.0

Metadata date 2023·03·30

Metadata point of contact
Communications, JNCC

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