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The status of Newfoundland and Labrador (NL) Atlantic Salmon populations are assessed relative to two reference points, defined on the basis of egg depositions, which separate three stock status zones (critical, cautious and healthy) as per the Fishery Decision-Making Framework Incorporating the Precautionary Approach. These reference points, the Limit Reference Point (LRP) and Upper Stock Reference (USR) point are set at 100% and 150% of the previously defined river-specific conservation egg deposition rate, respectively. In 2018, the status of Atlantic Salmon stocks within the NL Region (Salmon Fishing Areas 1-14B) was assessed using data collected from twenty-two rivers using a combination of salmon counting facilities (fishways and counting fences) and in-river snorkel surveys. Atlantic Salmon smolts migrating to sea were counted on five rivers in Newfoundland. The status of each monitored river is described by the designated stock status zone, % LRP achieved, and both short and long term trends in total adult salmon returns, smolt production and marine survival rates. Estimates of retained salmon in the 2018 recreational fishery were down by 70% and 58% compared to the previous generation averages in Newfoundland and Labrador, respectively. Labrador Food Social and Ceremonial (FSC) and subsistence fisheries harvests were estimated at 12,843 salmon in 2018 (8,762 small, 4,081 large), 7% less than the previous generation average. Of the twenty-two rivers monitored in 2018, one river was not included in the assessment due to an incomplete salmon count. Of the twenty-one other monitored rivers, sixteen had information on total returns over the previous generation (short term comparisons) and fifteen had information over the previous three generations (long term comparisons). Compared to the previous generation, total returns in 2018 were higher on three of four monitored rivers in Labrador and lower on five of twelve monitored rivers in Newfoundland. Compared to the previous three generations, total returns in 2018 were lower on one of four monitored rivers in Labrador and on five of eleven monitored rivers in Newfoundland. Conservation egg requirements were below the river-specific LRP (in the critical zone) on ten assessed rivers, between the LRP and USR on three assessed rivers, and above the river-specific USR on eight assessed rivers in the NL Region. Marine smolt survival is considered to be a major factor limiting the abundance of Atlantic Salmon within the NL Region. Smolt to adult survival of the 2018 smolt class ranged from <1% for Conne River to 9.3% for Western Arm Brook. [ABSTRACT FROM AUTHOR]

Atlantic salmon (Salmo salar) populations throughout the North Atlantic have declined in recent decades largely due to reduced marine survival, yet our understanding of marine distribution patterns and migratory routes remains limited. Here, we assigned archived individual samples (n  =   3891) collected over a half century (1968–2018) throughout the North Atlantic to region of origin using range-wide genetic assignment. In the Northwest Atlantic, the distribution of assignments reinforced the importance of the Labrador Sea as an aggregation area, with 73% of all reporting groups detected. Moreover, individuals from six European reporting groups were identified in the Northwest Atlantic, and detections decreased with decreasing latitude spanning an area from Greenland to southern Newfoundland. In the Northeast Atlantic, six North American reporting groups were detected in samples from around the Faroe Islands. Based on the distribution of samples, estimates of trans-Atlantic migration distance averaged 3861 and 2889 km for North American and European salmon respectively. Our analysis highlights the widespread importance of the Labrador Sea and Faroe Islands to the species marine distribution patterns, and the prevalence of long-distance trans-Atlantic migration. Ultimately, the results suggest that environmental conditions experienced by many Atlantic salmon populations span much of the North Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Patterns of change in angler participation and demographics were examined for the recreational Atlantic salmon, Salmo salar L., fishery in Newfoundland and Labrador, Canada. An analysis of a licence stub return system, 1994-2010, showed a significant decline in resident angler participation, but this was not consistent across all regions of the Province. Mean age of anglers increased significantly, varying from 39.0 years in 1994 to 46.5 years by 2010. In some regions, mean age rose by over 12 years since the mid-1990s, reflecting a decline in the recruitment of younger anglers. The return rate of angler logs also declined over time and was found to vary by age, sex and area of angler residence. Women and older anglers, and those living in specific rural areas had a greater tendency to return a record of their catch history than men and younger anglers. Identified changes in participation and demographics, which can affect exploitation and ultimately abundance, could be used to develop management measures that would maximise both harvest and socio-economic benefits to the varied users of the resource. [ABSTRACT FROM AUTHOR]

Atlantic salmon Salmo salar smolts ( n = 181) from two rivers were surgically implanted with acoustic transmitters and released to determine migration route, residency time and survival in a 50 km long estuarine fjord located on the south coast of Newfoundland, Canada. Data obtained from automated receivers placed throughout the Bay d'Espoir fjord indicated that migrating smolts used different routes to reach the outer areas of the fjord. The duration of time that smolts spent in the immediate estuary zone also differed between the two localities (7 and 17 days) although the total time smolts were resident in the fjord was similar and extensive (40 days). Many smolts were resident for periods of 4-8 weeks moving back and forth in the outer part of the fjord where maximum water depths range from 300 to 700 m. Survival in the estuary zone was greater for smolts with prolonged residency in estuarine habitat. Overall smolt survival to the fjord exit was moderately high (54-85%), indicating that the initial phase of migration did not coincide with a period of unusually high mortality. [ABSTRACT FROM AUTHOR]

Closure of the Newfoundland commercial Atlantic salmon,Salmo salarL., fishery in 1992 was the most restrictive measure introduced to help rebuild depressed local stocks of salmon. Here, the effects of the closure are evaluated by analysing trends in abundance since 1984, and estimates of survival in both freshwater and marine environments derived from enumeration of salmon at fish counting facilities. While freshwater production of smolts generally has been maintained, marine survival rates remain low (2–10%), and highly variable. Overall, total stock size differs little from that prior to the closure of the commercial salmon fishery. Spawning escapements have increased by a factor of 2 or 3 in some rivers, but in other areas total returns are lower on average than those prior to the fishery closure. Factors other than exploitation are contributing to lack of stock recovery, resulting in continued conservation concerns. [ABSTRACT FROM AUTHOR]

Dempson JB, Power M. Use of stable isotopes to distinguish farmed from wild Atlantic salmon, Salmo salar. Ecology of Freshwater Fish 2004: 13: 176–184. © Blackwell Munksgaard, 2004 Stable isotopes of carbon and nitrogen ( δ13C and δ15N) were examined in wild and aquaculture origin Atlantic salmon, Salmo salar, to evaluate their utility to identify escaped farmed fish. Samples of muscle tissue obtained from wild Conne River, Newfoundland, salmon were significantly more enriched in nitrogen ( δ15N: mean = 12.75; SD ± 0.38‰) but depleted in lipid corrected carbon ( δ13C′: mean = −20.51; SD ± 0.23‰) by comparison with aquaculture specimens obtained from Bay d'Espoir, Newfoundland ( δ15N = 10.96 ± 0.19‰; δ13C′ = −19.25 ± 0.17‰) resulting in a complete separation of the two groups. Aquaculture specimens differed in δ13C′ from analyses of commercial salmon diet by 0.24‰, within the enrichment range associated with trophic transfers, while the δ15N values in salmon muscle were enriched by 5.01‰. Although differences occurred in direct comparisons of white muscle and adipose tissue ( N = 49), the average δ13C′ and δ15N signatures varied in absolute amounts by only 0.5‰, supporting the use of adipose tissue as a nonlethal means to determine isotopic signatures of Atlantic salmon. [ABSTRACT FROM AUTHOR]

The effects of catch and release angling on survival of Atlantic salmon, Salmo salar L., at Conne River, Newfoundland, were investigated by retaining angled (n =49; experimental group) and trap-caught (n =20; control group) fish in holding cages for up to 40 days. Samples were obtained from 8 June to 4 July, 2000, and partitioned among four water temperature strata. Apart from not being angled, control fish were handled, tagged, and transferred to holding cages in a manner similar to angled salmon. Water temperatures and discharge were monitored throughout the duration of the study. Overall, 8.2% of salmon caught and released died, but 12% died among salmon angled in water temperatures ≥ 17.9 °C. No control fish died. There were no significant differences in time associated with angling, exposure to air, tagging, transfer to holding cages, nor total handling time between salmon that survived vs. those that died. Results of the study should encourage managers to continue to use catch and release as a viable tool in the management of Atlantic salmon stocks. [ABSTRACT FROM AUTHOR]

Potential impacts of climate warming on recreational fishing opportunities were addressed by assessing the frequency and extent that Atlantic salmon, Salmo salar L., rivers in Newfoundland have been closed over a 25-year period (1975 to 1999) because of warm water temperatures and low water levels. On average, approximately 28% of all salmon rivers were temporarily closed annually, with over 70% affected in some years. This has resulted in a loss of 35–65% of the potential fishing days available in some salmon fishing areas with the collective 1995 to 1999 period being impacted the most over the past two decades. Geographically, west and south-west coastal rivers were affected less from environmental closures than east and some south coast fishing areas. A trend for increased closures of rivers related to environmental reasons could reduce the economic importance of the recreational salmon fishery and also make it more difficult to assess the status of Atlantic salmon stocks, which is a requirement for conservation of the resource. [ABSTRACT FROM AUTHOR]

Marine exploitation rates were estimated for nine Newfoundland Atlantic salmon (Salmo salar L.) populations, separately for small and large salmon size components. Estimates were derived using counts of salmon returning to fish counting facilities rather than from tagging studies and thus adjustments were not required to account for tag loss, handling or tagging mortality, or tag reporting rates. For all stocks combined, the overall marine exploitation rate during the period 1984–1991 averaged 45.3% (29.6–57.1%) on small salmon and 74.2% (57.7–83.7%) on large salmon. These estimates are considered minimum values. Concerns related to declining salmon abundance resulted in the closure of the Newfoundland commercial salmon fishery in 1992. Results are discussed in relation to previous estimates derived from tagging, and highlight the importance of accounting for marine exploitation when examining trends in salmon survival and return data even when commercial fisheries have been closed. [ABSTRACT FROM PUBLISHER]

Five-thousand wild Atlantic salmon (Salmo salar L.) smolts from Conne River, Newfoundland, were captured during their downstream migration in May 1995, and transferred to an estuarine aquaculture rearing site at Roti Bay, 23 km away. Survival was monitored throughout the experiment. The greatest mortality occurred in July, approximately 6–8 weeks following transfer. Survival of smolts to one-sea-winter salmon was 18.5%, over four times higher than the average survival of wild salmon to Conne River during the past 6 years. Growth was monitored at monthly intervals until November 1995, with additional sampling in the spring and early summer of 1996. Survivors were split into two groups and released directly into the Bay d'Espoir fjord; one group was released 27–28 June 1996, at a site approximately 7 km from the mouth of Conne River. The second group was retained at Roti Bay and released 23 July 1996. Lotek radio transmitter tags were used in evaluating the success of the experiment by tracking migration timing and subsequent distribution of cage-reared salmon throughout the Conne River system. Approximately 80% returned to Conne River and 20% strayed to other streams. Less than 50% of the surviving fish were later accounted for in local Bay d'Espoir rivers. Results are discussed in relation to the utility of this technique to enhance salmon populations. [ABSTRACT FROM PUBLISHER]