The data we provide here have been assembled to categorise fish into feeding
guilds and determine change in populations of fish with different feeding
traits relevant to food web status assessment advocated by OSPAR.
We provide five datasets:
The first is a csv file titled ‘stomach data observations’ contains
observations from fish stomach contents of individual prey weight, prey
functional group (i.e., zooplankton, benthos, fish, nekton and other),
predator taxonomy, predator size, and the region and year the samples were
collected (Table 1; see Column_headers_readme.txt).
The second is a csv file titled ‘modelled stomach data’ provides predictions
from a linear mixed effects model of individual prey weight based on those
stomach contents observations, alongside modelled estimates of prey counts and
biomass which enable the full collation of stomach contents information to be
used in our feeding guild classification (Table 2; feeding guilds are
predatory categories assigned using cluster analysis on stomach content data;
see Thompson et al., 2023).
The third dataset is a shapefile titled ‘feeding guild responses in survey
data’ and provides haul-level estimates of feeding guild species richness,
numbers of fish and their biomass based on scientific trawl surveys from the
Northeast Atlantic (Tables 3-4).
The fourth is a shapefile titled ‘temporal changes in feeding guilds’ which
contains correlation coefficients and p values following Kendall’s τ
trend analysis between mean haul-level values of feeding guild biomass and
species richness for each assessment strata and year. Kendall’s τ scores of –1
to +1 represent a 100% probability of a decreasing or increasing trend,
respectively (Table 5).
The fifth dataset which provides the data to categorise fish taxa and body
mass classes into feeding guilds along with the number of stomach samples,
predator-prey mass ratios, average individual prey mass, average predator size
in cm, the % of different prey functional groups, axes scores from non-metric
multidimensional scaling analysis and the hierarchy of feeding guilds from
cluster analysis.