Effects of hookworms (Uncinaria sp.) on the early growth and survival of New Zealand sea lion (Phocarctos hookeri) pups

  title={Effects of hookworms (Uncinaria sp.) on the early growth and survival of New Zealand sea lion (Phocarctos hookeri) pups},
  author={B. Louise Chilvers and P{\'a}draig J. Duignan and Bruce C. Robertson and Aur{\'e}lie Castinel and Ian S. Wilkinson},
  journal={Polar Biology},
Parasites can have both direct and indirect impacts on organisms through changes in health, growth, reproductive success, behaviour and survival. This research investigates the effects of hookworms (Uncinaria sp.) on the growth and mortality of New Zealand sea lion (NZ sea lion, Phocarctos hookeri) pups between birth and 3 months of age. NZ sea lion pups that received ivermectin treatment to reduce their hookworm burden had higher growth rates. Hookworm infection had no significant effect on… 

Long-term survival and reproductive success of New Zealand sea lions (Phocarctos hookeri) treated with ivermectin as pups

The effect of disease and parasitism on the survival of NZ sea lions is apparent, contributing to early pup mortality, with potentially wider-ranging implications for juvenile survival and beyond.

The contrasting hidden consequences of parasitism: Effects of a hematophagous nematode (Uncinaria sp.) in the development of a marine mammal swimming behavior

The effects of hookworms (Uncinaria sp.) on the development of swimming capabilities in A. australis offered new insights to understand the contrasting effects of parasites on aquatic organisms, and the compensatory mechanisms employed by infected animals to avoid the worst consequences of parasitism.

The diversity and impact of hookworm infections in wildlife

  • M. SeguelN. Gottdenker
  • Environmental Science
    International journal for parasitology. Parasites and wildlife
  • 2017

Risk Factors for New Zealand Sea Lion (Phocarctos hookeri) Pup Mortality: Ivermectin Improves Survival for Conservation Management

Evidence is provided to support ivermectin treatment as a pup mortality mitigation strategy in New Zealand sea lions at Enderby Island and if applied to larger colonies where HV K. pneumoniae and hookworm impact pup survival, this intervention could have population-scale benefits for this endangered species.

Health assessment of free-ranging endangered Australian sea lion (Neophoca cinerea) pups: effect of haematophagous parasites on haematological parameters.

Developing Immune Profiles of Endangered Australian Sea Lion (Neophoca cinerea) Pups Within the Context of Endemic Hookworm (Uncinaria sanguinis) Infection

This study of the Australian sea lion is an example of an ecoimmunological approach to disease investigation, which can be applied to evaluate the impact of environmental and anthropogenic factors on susceptibility to infectious diseases in free-ranging species.

The population decline of the New Zealand sea lion Phocarctos hookeri: a review of possible causes

The most plausible hypotheses, based on available evidence, are that the observed decline, in particular, the decreasing number of breeding females in the Auckland Island population, is caused by fisheries-induced resource competition and fisheries-related by-catch.

Hookworm infection in the Australian sea lion (Neophoca cinerea)

This study investigates the identity of hookworms parasitising the Australian sea lion from three colonies in south Australia, Australia, using morphological and molecular techniques to describe a single novel species, Uncinaria sanguinis sp.

First Report of Uncinaria hamiltoni in Orphan Eastern Mediterranean Monk Seal Pups in Greece and Its Clinical Significance

The aim of this study was to document for the first time the presence of the hookworm Uncinaria hamiltoni in rehabilitated Mediterranean monk seal pups in Greece and the benefits of anthelmintic treatment as a tool for the conservation management of the species.



Epidemiology of hookworm (Uncinaria spp.) infection in New Zealand (Hooker’s) sea lion (Phocarctos hookeri) pups on Enderby Island, Auckland Islands (New Zealand) during the breeding seasons from 1999/2000 to 2004/2005

The examination of faeces for hookworm eggs in various age categories of sea lions revealed that only pups up to at least 3 months of age harboured adult hookworms in their intestines, and provided evidence for transmission occurring by the transmammary route in NZSLs.


This study provides valuable quantitative data on the natural causes of neonatal mortality in New Zealand sea lions that can be used in demographic models for management of threatened species.

Growth and survival of New Zealand sea lions, Phocarctos hookeri: birth to 3 months

This is the first study of the behaviour of females during parturition, pup birth mass and growth, and pre-weaning survival of NZ sea lions, Enderby Island, Auckland Islands during austral summer breeding seasons, 2001/2002 to 2003/2004.

First report and characterization of adult Uncinaria spp. in New Zealand Sea Lion (Phocarctos hookeri) pups from the Auckland Islands, New Zealand

This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri, collected from dead pups on Enderby Island during January and February, 2004.

A case of parasite-mediated competition? Phenotypic differentiation among hookworms Uncinaria sp. (Nematoda: Ancylostomatidae) in sympatric and allopatric populations of South American sea lions Otaria byronia, and fur seals Arctocephalus australis (Carnivora: Otariidae)

Hookworms in otariids are considered to meet the conditions and to fulfill the predictions set forth in the theoretical literature to define a likely case of host coexistence mediation by a shared

Observations in 2001 on hookworms (Uncinaria spp.) in otariid pinnipeds

Uncinaria spp. were recovered from the milk of California sea lions (Zalophus californianus) collected from the: (1) teats of a cow just after parturition (one parasitic third-stage larva, L3), (2)

Anthelminthic treatment negatively affects chick survival in the Eurasian Oystercatcher Haematopus ostralegus

No support is found for the hypothesis, based on between-species comparisons, that the presence of blood parasites is related to the saltiness of the environment, and all chicks and adults from both saltmarsh and adjacent freshwater habitat appeared free from blood parasites.

New Zealand sea lions Phocarctos hookeri and squid trawl fisheries: bycatch problems and management options

The New Zealand (NZ) sea lion Phocarctos hookeri is one of the world's most rare and highly localized pinnipeds. NZ sea lions only breed on New Zealand's subantarctic islands, with 86% of breeding

Further indication of viability of larvae of the hookworm (Uncinaria lucasi) for several years in tissues of northern fur seals (Callorhinus ursinus).

The fact that northern fur seal pups can be infected, by transmammary transmission, with larvae of U. lucasi capable of surviving for several years in tissues of cows, should be considered in management of these animals in captivity.

On the longevity of larvae of the hookworm Uncinaria lucasi in tissues of northern fur seals (Callorhinus ursinus)

The successful establishment of Brugia pahangi infection in neonate mice opens up the possibility of the ready availability of murine filarial infections and the best protocol for infecting animals and the subsequent development of adult worms and microfilariae.