Spawning and nursery grounds of forage fish in Welsh and surrounding waters from 2008 to 2020
The maps provide information on the location of spawning and nursery areas of several forage fish species in Welsh and surrounding waters, including the Irish and Celtic Seas and the western English Channel. The forage fish populations inhabiting these waters provide a key source of prey for many predators, such as marine mammal and seabird species, including several of conservation concern, that either breed or overwinter in the study area. Given that several forage fish species in the northeast Atlantic have shown major changes in distribution and abundance, up-to-date information on their recent distribution patterns is important, including on where the main nursery and spawning grounds are presently located. The maps are provided for eleven fish species that are prey to marine mammals and seabirds: herring, sprat, sardine, anchovy, sandeel, horse mackerel, mackerel and garfish as well as the gadoid species poor cod, whiting and cod. Using survey data from 2008 to 2020, hotspot maps were created for adults and juveniles of each of the species. Data on most of the species was sparse and some of the gears used in fisheries surveys were not designed to catch the target species. However, a hotspot methodology allowed data from different gears to be standardised and combined into a composite map which covered most of the study area during two periods of the year (Quarter 1 and Quarter 4). Maps largely corresponded to those previously reported although several new species were included for which no or limited historic maps were available, specifically sprat, poor cod and garfish.
dataset
https://data.cefas.co.uk/view/21465
name: Cefas Data Portal
description: The Cefas Data Portal contains metadata records and data sets available to download and connect to in support of our commitment to open science. Data is available in the following formats: Binary download, CSV.
function: download
CEFAS21465
https://data.cefas.co.uk
eng
biota
revision
2011-03-25
publication
2008-06-01
publication
2008-06-01
revision
2010-05-18
publication
2012-01-11
publication
2012-01-11
-10.00
-1.00
55.00
48.00
2008
2020
publication
2022-06-21
revision
2023-09-20
creation
2022-05-10
notPlanned
The focus of this study was spawning and nursery areas of forage fish in Welsh waters and surrounding shelf sea waters of the Celtic Sea, Irish Sea and the western English Channel. Publicly available data from international fisheries-independent surveys were supplemented by data collected on surveys by Cefas.Data from three different types of surveys were considered for this study: pelagic (acoustic), demersal otter trawl (also referred to as bottom trawl) and beam trawl surveys. The available surveys included in this study covered two periods, between February and April and between September and December. To ensure the largest possible spatial coverage, surveys in either period were pooled and termed Quarter 1 and Quarter 4. Distribution of juveniles in both Quarters (chapter 4) was considered representative of the nursery grounds for the species. However, the distribution of adult fish was only assumed to represent spawning areas during the Quarter that coincided with the spawning period. For some species the peak spawning periods fell outside the survey periods in which case no spawning maps could be produced. However, the adult fish distribution maps during both Quarters were included in this report. The survey data used in this work are limited to waters more than ~20 m deep and the maps of the spawning and nursery areas in this report are therefore not representative of estuarine and transitional waters. as the catchability of species varies by survey and, particularly, gear type, averaging the species abundance data from different surveys, would not have been appropriate. To compensate for differences between surveys in gear selectivity, we created distribution maps for each species and size category by using a hotspot approach. This was based on a threshold, applied to the abundance data for each survey year separately. For each species and size category, these binary hotspot maps were then averaged across the surveys and years within a period (Quarter). A full description of the hotspot methodology used can be found in Campanella and van der Kooij (2021) ( `https://waleslink.org/wp-content/uploads/2022/03/1.-Spawning-and-nursery-grounds-of-forage-fish_CEFAS-project-report-for-RSPB.pdf`_ ) .. _`https://waleslink.org/wp-content/uploads/2022/03/1.-spawning-and-nursery-grounds-of-forage-fish_cefas-project-report-for-rspb.pdf`: https://waleslink.org/wp-content/uploads/2022/03/1.-Spawning-and-nursery-grounds-of-forage-fish_CEFAS-project-report-for-RSPB.pdf
publication
2013-12-10
false
See the referenced specification
publication
2010-12-08
true
See the referenced specification
Unknown
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
originator
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
custodian
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
distributor
Royal Society for the Protection of Birds (HQ)
owner
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS)
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
pointOfContact
2023-09-20T11:52:45