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Vol. 45: 181–194, 2021 ENDANGERED SPECIES RESEARCH Published July 1 https://doi.org/10.3354/esr01129 Endang Species Res OPEN ACCESS Protected area use by two sympatric marine predators repopulating their historical range Marcus Salton1,6,*, Matt Carr2,7, L. Max Tarjan3,8, Justin Clarke1, Roger Kirkwood4,9, David Slip1,5, Robert Harcourt1 1Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia 2Department of Primary Industries, Jervis Bay Marine Park, New South Wales 2540, Australia 3Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California 95064, USA 4Research Department, Phillip Island Nature Parks, Cowes, Victoria 3922, Australia 5Taronga Conservation Society Australia, Mosman, New South Wales 2088, Australia 6Present address: Australian Antarctic Division, Department of Agriculture, Water and Environment, Kingston, Tasmania 7050, Australia 7Present address: Biodiversity Conservation Trust, Coffs Harbour, New South Wales 2450, Australia 8Present address: San Francisco Bay Bird Observatory, 524 Valley Way, Milpitas, California 95035, USA 9Present address: SARDI Aquatic Sciences, West Beach, South Australia 5024, Australia ABSTRACT: As large carnivores recover from over-exploitation, managers often lack evidence- based information on species habitat requirements and the efficacy of management practices, particularly where species repopulate areas from which they have long been extirpated. We investigated the movement and habitat use by 2 semi-aquatic carnivores (Australian fur seals Arc- tocephalus pusillus doriferus and New Zealand fur seals A. forsteri) at the northern end of their distributions in Australia, where after a long absence both are recolonising their historic range. We also assessed male fur seal habitat use overlap with terrestrial and marine protected areas (PAs). While at the margin of the range during winter and early spring, the males remained inshore close to terrestrial sites and where interactions with humans often occur. From early spring, the males from the range margin showed uniform movement toward colonies in the core of the species’ range prior to their breeding seasons. This contrasts with males tracked from the core of the species’ range that returned periodically to colonies during the year, and highlights the importance of range-wide monitoring of a species to inform conservation planning. Habitat use by some males included over 90% of a marine PA at the margin of the species’ range. Most terrestrial haul-outs used were within terrestrial PAs, while sites not protected were on the margin of the range. Despite wide-ranging habits, their dependence on coastal sites, where human access and activities can be regulated and more readily enforced, suggests that terrestrial and marine PAs will continue to play an important role in managing the recovery of these fur seals. KEY WORDS: Fur seal · Arctocephalus · Habitat use · Distribution · Population recovery · Recolonisation · Human−wildlife interaction 1. INTRODUCTION cal ranges (Chapron et al. 2014, Gompper et al. 2015, Karamanlidis et al. 2015, Martínez Cano et al. 2016). Conservation efforts have increased the population These changes often result in increased conflicts be- sizes of many large carnivores, and have either ex- tween humans and carnivores and among humans panded their ranges or allowed recovery into histori- (e.g.conservationistsandindustries)(Treves&Karanth © The authors 2021. Open Access under Creative Commons by *Corresponding author: [email protected] Attribution Licence. Use, distribution and reproduction are un - restricted. Authors and original publication must be credited. Publisher: Inter-Research · www.int-res.com 182 Endang Species Res 45: 181–194, 2021 2003, Miller et al. 2013). Interactions at expanding ferent extents depending upon intent. For example, range margins can be challenging for humans, who within Australia’s marine park network, there may are more often ill prepared to manage such change be 4 or more tiers of protection zones, ranging from (Ciucci & Boitani 1998, Trouwborst et al. 2015, More- no-take zones to areas where only certain types of house & Boyce 2017). While lethal methods are often fishing (e.g. commercial) are prohibited (Roberts et deployed to alleviate conflict, they are counter-pro- al. 2018). These zones can focus human activities into ductive for conservation of recovering species and do areas where they will cause the least disruption to not necessarily reduce conflicts (Stahl et al. 2001, animals, whilst allowing compatible activities to con- Treves 2009). Non-lethal management alternatives tinue. With effective mitigation of negative human− (e.g. Shivik 2004) are important to re solve human− carnivore interactions, protected areas can help sus- carnivore conflicts and create a future where humans tain populations (Barnes et al. 2016), directly im - and competing wildlife coexist (Woodroffe et al. prove their demographic parameters (Gormley et al. 2005). Accordingly, there is growing interest in iden- 2012) and support ecosystem recovery (Prato et al. tifying habitat selection by large carnivores and lo- 2013). This suggests that conservation management cating potential ‘conflict hotspots’ (Miller 2015). This of carnivores moving back into their historical ranges can help prioritise limited management re sources could be improved if existing protected areas with into areas with high-risk human− carnivore interac- suitable habitat for essential activities by these carni- tions. In this study, we investigated the movements of vores could be identified. individuals from recovering populations of large Semi-aquatic species have a strong reliance on semi-aquatic carnivores, fur seals, which are often coastal habitats where we now also have high-den- seen by fishermen as competitors. We focussed on a sity human populations, so it is not surprising that region where 2 species have re cently greatly expan - they have a long history of interactions with humans. ded their geographic ranges after a long absence Many species have been harvested, or culled to resulting from sealing in the 19th and early 20th cen- reduce fisheries and aquaculture interactions, but turies. We quantified habitat use and compared mar- are now recovering (Gerber & Hilborn 2001, Kirk- ine and terrestrial areas in relation to their protected wood & Goldsworthy 2013, Magera et al. 2013). In status for conservation planning. Australia, the New Zealand fur seal Arctocephalus Protected areas are a widely used, multi-purpose forsteri (also called long-nosed fur seal, Shaughnessy management tool (J. E. Watson et al. 2014). Protected & Goldsworthy 2015) and the Australian fur seal areas may conserve biodiversity and ecosystem func- A. pusillus doriferus are both recovering from past tions, protect natural and cultural features, preserve exploitation (Shaughnessy et al. 2015, McIntosh et al. human assets (e.g. forests and water resources) and 2018b). Both species are protected by national law minimise human impacts. By regulating human access under the Environmental Protection and Biodiversity and activities, protected areas can play a role in miti- Conservation Act 1999 and are the subjects of a gating negative interactions with wildlife and aid the national strategy to minimise adverse interactions recovery of large carnivores (Linnell et al. 2005, with human activities (National Seal Strategy Group Chapron et al. 2014, Santini et al. 2016). Protected ar- 2007). As with other semi-aquatic species, interac- eas are used in terrestrial and marine contexts, and tions between fur seals and humans occur on land when located along a coastline, they can assist in man- and at sea, with fisheries, aquaculture and tourism aging human impacts on adjacent marine and terres- industries and the general public (Kirkwood et al. trial habitats (Stoms et al. 2005). These areas are typi- 2003, Shaughnessy et al. 2003, Robinson et al. 2008b), cally not designed specifically to mitigate interactions and are likely to increase as seal populations con- between humans and wide-ranging species, because tinue to recover and industries develop (Schumann their small boundaries do not sufficiently capture the et al. 2013). These interactions can result in economic species’ large foraging ranges (Hooker et al. 2011). loss or injury to humans, and stress, changed behav- However, despite many large carnivores ranging iour, injury or death of seals. Therefore, it is impor- widely to feed, they often use discrete areas for essen- tant to have accurate information to correctly assess tial activities such as breeding, moulting, resting and seal− human interactions and their consequences as avoiding predators; for these activities, discrete pro- seal populations recover (Costalago et al. 2019). tected areas may have beneficial effects (Huon et al. Currently, little information is available on the 2015, McAllister et al. 2015, Pérez-Jorge et al. 2015). movements and habitat use by the 2 fur seal species Protected area design often includes multiple use in Australasia on which to base management plans, zoning where human activities are restricted to dif- as most information is focussed on females (Harcourt Salton et al.: Protected area use by recovering predators 183 et al. 2001, Kirkwood & Goldsworthy 2013, Hoskins the frequency of visitation to different habitats, we et al. 2017). Most studies on male movements and identified areas likely to be important to the seals habitat