Future for Narwhals
Migrating narwhals
Specialisations in feeding and habitat choice,
small population size, narrow geographic distribution and high site fidelity are key components of narwhal biology that cause them to be more vulnerable to climate change than other arctic marine species [6;8;9].
Reductions in open water, cracks and leads due to an increase in sea ice intensifies narwhals’ vulnerability to mass-mortality events [1;3;6]. These events occur when narwhals cannot access sufficient amounts of oxygen due to expansive ice cover [1;3;6]. Reduction in leads and cracks create an enormous habitat constraint for narwhals, which can have significant negative effects on population dynamics, migration and feeding [1;3;6].
Migration is affected by the extent and position of sea ice, where increases in ice result in narwhals having to travel new routes or increased distances to maintain access to oxygen through shifting leads and cracks [1;3;6]. Due to their high site fidelity, narwhals are unlikely to radically shift their migration patterns and seasonal grounds under the rapid effects of anthropogenic climate change [3;6].
small population size, narrow geographic distribution and high site fidelity are key components of narwhal biology that cause them to be more vulnerable to climate change than other arctic marine species [6;8;9].
Reductions in open water, cracks and leads due to an increase in sea ice intensifies narwhals’ vulnerability to mass-mortality events [1;3;6]. These events occur when narwhals cannot access sufficient amounts of oxygen due to expansive ice cover [1;3;6]. Reduction in leads and cracks create an enormous habitat constraint for narwhals, which can have significant negative effects on population dynamics, migration and feeding [1;3;6].
Migration is affected by the extent and position of sea ice, where increases in ice result in narwhals having to travel new routes or increased distances to maintain access to oxygen through shifting leads and cracks [1;3;6]. Due to their high site fidelity, narwhals are unlikely to radically shift their migration patterns and seasonal grounds under the rapid effects of anthropogenic climate change [3;6].
If narwhals were to persist in the arctic, they would need to break their tight site fidelity and move to areas with a greater proportion of open water [3]. This movement, if possible, would also depend on prey availability [3]. They would need to change the timing of their migration to early periods within the season so as to avoid being caught in expansive pack ice.
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As narwhals have been found to be operating close to their performance maximum (i.e. dive to the deepest levels, remain submerged for the longest amount of time to find leads and cracks), they most likely have little to no flexibility to adjust their behaviours in response to a rapidly changing environment [9].
Indirect effects within the Arctic environment may also affect the survivorship of narwhal populations [7]. These include competition with invasive species, predation and disease [7]. In conjunction with climate change, human induced factors such as harvesting are taking their toll on narwhal populations [6]. If harvesting is to continue, sustainable levels must be implemented. Increased shipping throughout narwhal habitats is known to disturb their behaviours, with noise pollution particularly affecting their use of sounds for communication and navigation [7].
If effective conservation strategies are not implemented and narwhals are unable to apply changes to their behaviour, it is likely that anthropogenic climate change will drive them to extinction.
Indirect effects within the Arctic environment may also affect the survivorship of narwhal populations [7]. These include competition with invasive species, predation and disease [7]. In conjunction with climate change, human induced factors such as harvesting are taking their toll on narwhal populations [6]. If harvesting is to continue, sustainable levels must be implemented. Increased shipping throughout narwhal habitats is known to disturb their behaviours, with noise pollution particularly affecting their use of sounds for communication and navigation [7].
If effective conservation strategies are not implemented and narwhals are unable to apply changes to their behaviour, it is likely that anthropogenic climate change will drive them to extinction.