Heart rate and swimming activity as indicators of post-surgical recovery time of Atlantic salmon (Salmo salar)

Background Fish telemetry using electronic transmitter or data storage tags has become a common method for studying free-swimming fish both in the wild and in aquaculture. However, fish used in telemetry studies must be handled, anaesthetised and often subjected to surgical procedures to be equipped with tags, processes that will shift the fish from their normal physiological and behavioural states. In many projects, information is needed on when the fish has recovered after handling and tagging so that only the data recorded after the fish has fully recovered are used in analyses. We aimed to establish recovery times of adult Atlantic salmon (Salmo salar) after an intraperitoneal tagging procedure featuring handling, anaesthesia and surgery. Results Based on ECG and accelerometer data collected with telemetry from nine individual Atlantic salmon during the first period after tagging, we found that heart rate was initially elevated in all fish and that it took an average of ≈ 4 days and a maximum of 6 days for heart rate to return to an assumed baseline level. One activity tag showed no consistent decline in activity, and two others did not show strong evidence of complete recovery by the end of the experiment: baseline levels of the remaining tags were on average reached after ≈ 3.3 days. Conclusion Our findings showed that the Atlantic salmon used in this study required an average of ≈ 4 days, with a maximum interval of 6 days, of recovery after tagging before tag data could be considered valid. Moreover, the differences between recovery times for heart rate and activity imply that recovery time recommendations should be developed based on a combination of indicators and not just on e.g. behavioural observations.

Heart rate and swimming activity as indicators of post-surgical recovery time of Atlantic salmon (Salmo salar)

Background: Fish telemetry using electronic transmitter or data storage tags has become a common method for studying free-swimming fish both in the wild and in aquaculture. However, fish used in telemetry studies must be handled, anaesthetised and often subjected to surgical procedures to be equipped with tags, processes that will shift the fish from their normal physiological and behavioural states. In many projects, information is needed on when the fish has recovered after handling and tagging so that only the data recorded after the fish has fully recovered are used in analyses. We aimed to establish recovery times of adult Atlantic salmon (Salmo salar) after an intraperitoneal tagging procedure featuring handling, anaesthesia and surgery. Results: Based on ECG and accelerometer data collected with telemetry from nine individual Atlantic salmon during the first period after tagging, we found that heart rate was initially elevated in all fish, and that it took an average of ≈4 days and a maximum of 6 days for heart rate to return to an assumed baseline level. One activity tag showed no consistent decline in activity, and two others did not show strong evidence of complete recovery by the end of the experiment: baseline levels of the remaining tags were on average reached after ≈ 3.3 days. Conclusion: Our findings showed that the Atlantic salmon used in this study required an average of ≈ 4 days, with a maximum interval of 6 days, of recovery after tagging before tag data could be considered valid. Moreover, the differences between recovery times for heart rate and activity imply that recovery time recommendations should be developed based on a combination of indicators and not just on e.g. behavioural observations.

Heart rate and swimming activity as indicators of post-surgical recovery time of Atlantic salmon (Salmo salar)

Background: Fish telemetry using electronic transmitter or data storage tags has become a common method for studying free-swimming fish both in the wild and in aquaculture. However, fish used in telemetry studies must be handled, anaesthetised and often subjected to surgical procedures to be equipped with tags, processes that will shift the fish from their normal physiological and behavioural states. In many projects, information is needed on when the fish has recovered after handling and tagging so that only the data recorded after the fish has fully recovered are used in analyses. We aimed to establish recovery times of adult Atlantic salmon (Salmo salar) after an intraperitoneal tagging procedure featuring handling, anaesthesia and surgery. Results: Based on ECG and accelerometer data collected with telemetry from nine individual Atlantic salmon during the first period after tagging, we found that heart rate was initially elevated in all fish, and that it took an average of ≈4 days and a maximum of 6 days for heart rate to return to an assumed baseline level. Although activity levels assessed from acceleration appeared to be less affected by the tagging procedure, baseline levels were on average reached after ≈ 5 days for this parameter. Conclusion: Our findings showed that the Atlantic salmon used in this study required an average of ≈ 4 days, with a maximum interval of 6 days, of recovery after tagging before tag data could be considered valid. Moreover, the differences between recovery times for heart rate and activity imply that recovery time recommendations should be developed based on a combination of indicators and not just on e.g. behavioural observations.

Applying a knowledge–action framework for navigating barriers to incorporating telemetry science into fisheries management and conservation: a qualitative study

Telemetry studies have produced fundamental knowledge on animal biology and ecology that has the potential to improve management of aquatic resources such as fisheries. However, the use and integration of telemetry-derived knowledge into practice remain tenuous, so we surveyed 212 fish telemetry experts to understand existing barriers for incorporating telemetry-derived knowledge into fisheries management practices. We apply a sociological knowledge–action framework to structure the findings, which revealed four primary challenges to integrating telemetry findings into management: (1) the perceived uncertainties and unclear relevance of telemetry findings; (2) the underlying motivations and constrained rationalities of actors that can lead to inaction or suboptimal decisions; (3) the constraints of institutions, governance structures, and lack of organizational support, and (4) time and mismatches in scale, culture, and world views. On a more positive note, the relational dimension (collaboration, trust, and relationship building) appears to be important for overcoming and avoiding barriers. We further provide recommendations to navigate these perceived barriers and argue that these lessons also apply to other fields of applied ecology, conservation, and resource management.

To share or not to share in the emerging era of big data: perspectives from fish telemetry researchers on data sharing

The potential for telemetry data to answer complex questions about aquatic animals and their interactions with the environment is limited by the capacity to store, manage, and access data across the research community. Large telemetry networks and databases exist, but are limited by the actions of researchers to share their telemetry data. Promoting data sharing and understanding researchers’ views on open practices is a major step toward enhancing the role of big data in ecology and resources management. We surveyed 307 fish telemetry researchers to understand their perspectives and experiences on data sharing. A logistic regression revealed that data sharing was positively related to researchers with collaborative tendencies, who belong to a telemetry network, who are prolific publishers, and who express altruistic motives for their research. Researchers were less likely to have shared telemetry data if they engage in radio and (or) acoustic telemetry, work for regional government, and value the time it takes to complete a research project. We identify and provide examples of both benefits and concerns that respondents have about sharing telemetry data.