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Table 1 Experimental details and observed detections of smolts per receiver array

From: Quantifying the effects of post-surgery recovery time on the migration dynamics and survival rates in the wild of acoustically tagged Atlantic Salmon Salmo salar smolts

  Day-released Night-released Spring hatchery Winter hatchery
Dates of collection (n) May 17 (22); May 18 (9); May 19 (1) May 18 (19); May 19 (10) Oct 9, 2015 (31) from Miner’s Bridge; Oct 13, 2015 (52) from Trout Brook
Dates taken off feed (n) May 17 (22); May 18 (9); May 19 (1) May 18 (19); May 19 (10) May 15 March 6–March 8; May 15
Dates of tagging (n) May 18 (22); May 19 (9);
May 20 (1)
May 19 (19); May 20 (10) May 19 (29) March 8 (30)
Dates of release (n) May 18 (22); May 19 (9); May 20 (1) May 19 (19); May 20 (10) May 19 (29) May 19 (29)
Post-surgical recovery time (mean days ± SD) 0.17 ± 0.06 0.42 ± 0.08 0.27 ± 0.06 71.43 ± 0.01
Size at tagging (median (min–max))
 Fork length (mm) 136 (129–182) 141 (130–169) 172 (131–202) 149 (130–163)
 Mass (g) 23.9 (17.3–54.6) 26.1 (19.8–43.9) 45.6 (31.1–67.5) 37.0 (24.7- 50.1)
 Tag burden (%) 8.38 (3.66–11.56) 7.66 (4.56–10.10) 4.38 (2.96–6.43) 5.41 (3.99- 8.10)
Number of individual fish detected (detections inferred from a predator fish inducing bias in relation to total tags inferred ingested by a predator and inducing bias)
 At release 32 29 29 29
 At Cassilis 26 (0 of 4) 22 (0 of 4) 13 (0 of 2) 23 (0 of 4)
 At Nelson 20 (2 of 4) 17 (3 of 4) 10 (1 of 2) 18 (2 of 4)
 At Loggieville 16 (4 of 4) 16 (4 of 4) 10 (2 of 2) 17 (4 of 4)
 At Outer Bay 8 (1 of 4) 9 (1 of 4) 4 (0 of 2) 10 (0 of 4)
 At Strait of Belle Isle 3 (0 of 4) 5 (0 of 4) 1 (0 of 2) 6 (0 of 4)
 At Strait of Belle Isle North 1 (0 of 4) 3 (0 of 4) 1 (0 of 2) 7 (0 of 4)
  1. For the detections, the values in parentheses are the number of tags detected at each array inferred to be of a smolt tag ingested by a predator which induced predation bias rather than of a free-swimming smolt relative to the total number of unique tags which were inferred to have been ingested by a predator and induced predation bias over the whole migration period. Fork length, mass tag burden measured on March 8th for Winter hatchery treatment while remaining treatment groups were measured between May 18th and the 20th