Leopard seals, Hydrurga leptonyx de Blainville, 1820 (Mammalia Phocidae) have variable spots on their pelage, allowing for identification of individuals.We monitored a subset of spots (n=40) on the face and neck of an adult female leopard seal residing in New Zealand.We compared images that were 1,701 days (~4 years and 8 months) apart.The use of scars, acquired from wounds, allowed for cross-matching and confirmation that this was the same individual.We investigated if the spots were more visible when the animal was wet or dry.We found that all 40 spots were visible during this time period and when the animal was both wet and dry.However, they were better defined, and therefore more visible, when the pelage was wet.Additionally, we identified a number of new and emerging spots, none of which masked or obscured the 40 aforementioned spots.These changes illustrate that diligence must be applied when matching individuals over long periods, to ensure that mis-matches and missed matches do not occur.Our findings do not invalidate photo-ID studies for leopard seals, rather they show that this is a robust system of identification, as spots were not lost over time and spot patterns were an effective tool for both individual identification and observing pigmentation change.

Despite the ecological importance of leopard seals ( Hydrurga leptonyx ) as apex marine predators, little is known about their reproductive biology. To address this paucity, we reviewed leopard seal birth and pup records and applied a standardised age-class classification system to differentiate between births/newborns (offspring ≤ 14 days old) and pups (> 14 days but < 6 months old). We compiled 19 birth/newborn and 141 pup records and examined their occurrence by month, region, substrate, birth-specific attributes (i.e. birth observations, fresh umbilicus or placental), standard length, weight, presence of mother, presence of lanugo, sex, status (e.g. born alive) and fate. These records indicate that leopard seal births occur between September and December, with peak records from September to November, whilst pup records peaked between August and December. The regions with the most birth/newborn records were the sub-Antarctic Islands (31.6%) and Chile (31.6%), followed by Antarctica (15.8%), New Zealand (15.8%) and the Falkland Islands (5.3%). Pups were recorded predominantly in the sub-Antarctic Islands (54.6%), followed by the Antarctic (42.6%), Chile (2.1%) and Australia (0.7%). Whilst leopard seal birth records were predominantly on ice, they were also found on terra firma . The northernmost published leopard seal birth records occurred in New Zealand whilst the northernmost published leopard seal pup records occurred in Australia. This study contradicts the long-standing hypothesis that leopard seals only give birth on Antarctic pack ice, and instead, here we indicate that 84.2% and 57.4% of collated leopard seal birth and pup records, respectively, occur outside of Antarctica. Our records illustrate the importance of northern regions as part of the leopard seal’s range. We emphasise the need to conduct research focused on the reproductive biology of this keystone species throughout its range and that future management of leopard seal populations should also consider their northern range.

The >9.5-year residency of an adult female leopard seal, Hydrurga leptonyx de Blainville, 1820 (Mammalia Phocidae) in New Zealand (NZ) provided an opportunity to investigate this species in the framework of human-wildlife conflicts and management.We examined >2,000 sighting records and collated observations of this leopard seal.We qualitatively describe conflicts originating from both the humans and leopard seal's perspectives.Humans created conflicts for the leopard seal by providing misinformation about the species (and therefore negatively influencing public perception), making proposals or threats to disturb/harm, and causing inconvenience, tension, disputes, disturbance and harm to her.Conversely, the leopard seal created conflicts for humans including, causing inconveniences, tension, damage to property and disturbance.Short-term mitigation tools along with longer-term preventive strategies to reduce, mitigate and/or eliminate these conflicts are provided and we recommend that the NZ Government Authorities, who are legally mandated to protect the species, take the lead in implementing these in collaboration with stakeholders.Implementation of these tools and strategies, in a proactive rather than reactive manner, will assist with protection and management of leopard seals in all areas where they cohabitate with humans (both within NZ and internationally).

Leopard seals ( Hydrurga leptonyx ) are top-order predators that prey on a wide variety of species including crustaceans, cephalopods, fishes, birds, and pinnipeds. While multiple diet studies have been conducted worldwide, there are no previous accounts of leopard seals predating on chondrichthyans. As part of a wider study on the diet of leopard seals in New Zealand (NZ) waters, researchers and citizen scientists recorded 39 observations of predation and collected 127 scats (166 total records) between 1942 and 2019. Predation on chondrichthyans was detected in 23.1% ( n = 9) of observations of predation and 7.1% ( n = 9) of scats (the latter via morphological examination and DNA sequencing). From both observations of predations and scats, three chondrichthyan species or genus were identified; elephantfish ( Callorhinchus milii ), ghost sharks ( Hydrolagus spp.) and spiny dogfish ( Squalus acanthias ). While this is the first published record of leopard seals feeding on chondrichthyans, the relatively high frequency of occurrence within our NZ records, and that certain individuals appeared to target this type of prey, indicates that these species could constitute a substantial, or important, part of the diet for some leopard seals in this region. As chondrichthyans form an important part of the NZ marine ecosystems, our recognition of an additional top-order predator of these species contributes to understanding the overall health of, and future impacts of predators on, the wider NZ marine ecosystem.

In contrast to previous reports that leopard seals (Hydrurga leptonyx) are rare vagrants to New Zealand, we show that this species is a regular member of the marine fauna of this region. We present a first analysis from the New Zealand Leopard Seal Database – an extensive collation of 2,711 records of leopard seals within New Zealand between 1200 and 2018. Of these records, 51.2% (n = 1,408) were photographic. Leopard seal sightings have increased over time and been reported in all seasons and regions of New Zealand. Sightings are predominantly of adult individuals of good or excellent body condition, which differs to previous hypotheses suggesting that leopard seals visiting New Zealand shores are primarily juvenile animals in poor health condition. A total of 176 unique individuals have been identified in the New Zealand Leopard Seal Catalogue between 2014 and 2018 and preliminary results indicate that numbers per annum have continued to increase over time. Three leopard seal births and a number of juvenile animals (34% of the NZ records) have been documented. Considering the information presented here and the current definitions in the New Zealand Threat Classification System, the threat status of leopard seals within New Zealand waters should be reclassified from Vagrant to Resident.