Increased alertness behavior in Australian fur seals (Arctocephalus pusillus doriferus) at a high vessel traffic haul‐out site

Abstract

Vessel impacts on marine mammals are of growing concern, and marine mammals in urbanized marine environments are at particular risk of exposure. Port Phillip Bay (Victoria, Australia) is one such environment, in which Australian fur seals (AUFS; Arctocephalus pusillus doriferus) haul‐out to rest, yet little is known about the impacts of vessels on resting seals. We used remote camera traps to investigate the influence of vessel traffic on AUFS behavior at a nonbreeding haul‐out site. Environmental, temporal, and vessel‐related variables were all associated with changes in AUFS alertness at this site. All vessel types elicited increased alertness above base‐line levels (25%), with recreational and commercial motorized vessels associated with a 5.7%–10.8% increase in alertness. Unidentified vessels, the government vessel, and kayaks were associated with significantly increased alertness of 21.7%, 46.4%, and 60.7%, respectively, though accounted for only 6.2% of vessel observations. Vessels breaching current approach regulations (<5 m) showed a 32% increase in alertness, significantly higher than nonbreach approaches. Partial and complete flushing of the platform was rare, occurring in 1.0% of images analyzed. These results suggest that vessels do elicit a response from AUFS at this haul‐out site, and that further monitoring of vessel activity and compliance is required.

Behavior Change in Urban Mammals: A Systematic Review

“…Likewise, urban Eurasian red squirrels demonstrated the ability to assess risk levels of various approaching objects (e.g., humans and conspecific decoys) and modulated their FID accordingly (Uchida et al, 2019(Uchida et al, , 2020. Finally, a study on Australian fur seals (Arctocephalus pusillus doriferus) found that seals modulated their alert response based on vessel type and whether or not vessels conformed with mandated approach distance thresholds-indicating that the seals learned the legal distance ships were able to approach (Speakman et al, 2020).…”

Table_4.DOCX

“…Likewise, urban Eurasian red squirrels demonstrated the ability to assess risk levels of various approaching objects (e.g., humans and conspecific decoys) and modulated their FID accordingly (Uchida et al, 2019(Uchida et al, , 2020. Finally, a study on Australian fur seals (Arctocephalus pusillus doriferus) found that seals modulated their alert response based on vessel type and whether or not vessels conformed with mandated approach distance thresholds-indicating that the seals learned the legal distance ships were able to approach (Speakman et al, 2020).…”