The fate of intracoelomic acoustic transmitters in Atlantic salmon (Salmo salar) post-smolts and wider considerations for causal factors driving tag retention and mortality in fishes

Table 1 Statistical output for the effect of tag type (i.e., sham control, V7 or V8 acoustic tags) and sex on Δ length and specific growth rate (SGR) in Atlantic salmon (Salmo salar) post-smolts monitored over a 92-day holding period.

Response Variable	Term	Estimate	Standard error	df	t value	P value
Δ Length
Linear mixed model—fixed effects
	(Intercept)	0.019	0.004	92.35	4.36	< 0.001
	Δ Weight	0.212	0.011	165.40	18.79	< 0.001
	Tag type—V7	− 0.004	0.002	165.00	− 2.05	0.042
	Tag type—V8	− 0.001	0.002	165.90	− 0.56	0.580
	Sex—M	0.003	0.002	166.00	1.70	0.092
	Surgeon	0.002	0.001	165.10	2.51	0.013
Pair wise contrasts
	Sham—V7	0.004	0.002	165	2.05	0.104
	Sham—V8	0.001	0.002	166	0.55	0.846
	V7–V8	-0.003	0.002	166	− 1.55	0.271
SGR
Linear mixed model—fixed effects
	(Intercept)	0.783	0.048	10.12	16.47	< 0.001
	Tag type—V7	− 0.109	0.031	166.06	− 3.48	< 0.001
	Tag type—V8	− 0.069	0.031	166.35	− 2.24	0.026
	Sex—M	0.046	0.026	166.64	1.79	0.076
	Surgeon	− 0.004	0.016	166.06	− 0.25	0.800
Pair wise contrasts
	Sham—V7	0.109	0.031	166	3.47	0.002
	Sham—V8	0.069	0.031	166	2.24	0.068
	V7–V8	− 0.040	0.032	167	− 1.27	0.415

A linear mixed effects model with the fixed effects of tag type, sex, surgeon, and Δ weight (Δ length model only), and a random effect of holding tank. Tag type effects were addressed using Tukey pairwise contrasts. Bolded rows represent statistically significant results (α = 0.05)

ISSN: 2050-3385