Walsh and Guida: Fish and macro-invertebrate assemblages near wind energy areas 
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Figure 2 
Average individual weight (g) of taxa that had at least a 5% frequency of 
occurrence in collections made with the beam and bottom trawls on the 
northeast U.S. continental shelf in 2014. A Student’s A test was used to 
examine whether the sizes of individuals were significantly different be¬ 
tween the collections made with the 2 gear types. An asterisk (*) indicates 
a taxa for which a difference in individual size between collections by gear 
type was considered significant (Bonferroni corrected P-value: <0.0045). 
Error bars indicate standard errors of the means. 
bottom trawl (Fig. 3A). Both average proportion of taxa 
per station (76.6%) and average individual weights by 
taxon (23.4%) contributed to assemblage variation (Fig. 
3, B and C). The beam trawl collected significantly 
smaller individuals of most taxa, and the bottom trawl 
stations in the NJ WEA had spiny dogfish with larger 
average individual weights (Fig. SC). 
Comparison of assemblages by wind energy area 
The separate analyses of collections made with each 
gear type indicated that the fish and macro-inverte¬ 
brate communities varied across several spatial scales 
and that assemblage varied among and within WEAs. 
Four CA dimensions explained at least 50% of the 
variation in average proportion of a taxon per station 
and estimated average individual weight of a taxon per 
station for analyses of both the beam and bottom trawl 
collections. Again, the first 2 dimensions described the 
overall pattern of assemblages associated with each 
gear type (Figs. 4 and 5). 
The first 2 dimensions of the CA for the beam trawl 
described 30.2% of the variance in assemblages with 
eigenvalues of 0.72 and 0.64 respectively. Taxa that 
contributed significantly (>1%; Table 
2) to the ordination highlight the dif¬ 
ferent communities across the large 
spatial scale (north to south) and 
within WEAs (Fig. 4). The 3 northern 
WEAs (RIMA-MA, NY, NJ) were dis¬ 
tinct from the VA WEA, and separated 
along the second dimension (Fig. 4A), 
and average proportion of taxa per sta¬ 
tion (85.3%) contributed most to the 
separation in assemblage structure 
(Fig. 4B). The VA WEA had higher pro¬ 
portions of spotted hake ( Urophycis 
regia), Prionotus spp., Etropus spp., 
Pagrus spp., gastropods, bivalves, 
and braehyuran crabs (Fig. 4B). The 
northern WEAs overlapped each other, 
but did show some separation along 
both dimensions, particularly for the 
RIMA-MA WEA (Fig. 4A), indicating 
variation of communities at smaller 
spatial scales (e.g., within WEAs). 
Both average proportion of taxa per 
station (63.7%) and average individu¬ 
al weights of taxa per station (36.3%) 
contributed to the variation (Fig. 4, B 
and C). Stations in the lower left quad¬ 
rant (Fig. 4A) had higher proportions 
and larger average individual weight 
of Leucoraja spp. (Fig. 4, B and C). The 
stations on the lower right quadrant of 
the ordination, located mostly in the 
RIMA-MA WEA (Fig. 4A), had higher 
proportions of poriferan sponges and 
larger average individual weight of 
braehyuran crabs (Fig. 4, B and C). 
Stations near the origin (Fig. 4A) had higher propor¬ 
tions of caridean shrimp, common sand dollar, and spe¬ 
cies of the order Pleurobranchomorpha (Fig. 4B). Both 
the sea scallop and the red hake are close in ordination 
space near the origin, but are not labeled. 
The first 2 dimensions of the CA for the bottom trawl 
explained 32.5% of the variance in assemblages, with 
eigenvalues of 0.47 and 0.27, respectively. Taxa that 
contributed significantly (>3%; Table 3) to the ordina¬ 
tion highlight the differences among the assemblages 
(Fig. 5). The NY and NJ WEAs were distinct from the 
RIMA-MA WEA, and separated along the first dimen¬ 
sion (Fig. 5A). Average individual weight of a taxon per 
station (85.8%) contributed most to the separation in 
assemblage structure along the first dimension (Fig. 
5C). Larger individuals of horseshoe crab (Limulus 
Polyphemus), and spiny dogfish were caught in the NY 
and NJ WEAs, and larger individuals of longhorn scul- 
pin, ocean pout, sea raven (Hemitripterus americanus), 
and yellowtail flounder were caught in the RIMA-MA 
WEA (Fig. 5C). Additionally, the RIMA-MA WEA had 
higher station proportions of scup ( Stenotomus chrys- 
ops) and haddock than the NY and NJ WEAs (Fig. 
5B). Variability in assemblage structure also occurred 
