Justification of Red List Category
This species has been classified as Endangered owing to very rapid population decreases over the last three generations (30 years) throughout its range. Precise reasons for the declines are poorly known, but changes in sea temperature, competition and incidental capture in fisheries and introduced predators are all likely to be implicated.
Population trends are still poorly known due to the remote nature of these islands. The global population however is estimated at around 240,300 breeding pairs (Cuthbert 2013, TdC and RSPB unpubl. data) with the majority of breeding pairs being found on Gough Island and islands in the Tristan da Cunha group (68,000 pairs on Middle Island -2015-, 64,700 pairs on Gough -2006-, 16,000 pairs on Nightingale -2015-, 54,000 pairs on Inaccessible -2009- and 3600 pairs on Tristan da Cunha -2015- islands; Cuthbert 2013, RSPB and TdC unpubl. data). Numbers indicate that populations are still declining (TdC and RSPB unpubl. data). At the species’ two breeding locations in the Indian Ocean, Amsterdam (25,000 pairs, 1993) and St. Paul (9,000 pairs, 1993) islands numbers have been declining at an average rate of 3-4% since the early 1970s (CEBC-CNRS unpubl. data). Overall, recent population models indicate that over the past 37 years (three generations) the numbers of Northern Rockhopper Penguins have declined by 57% (Birdlife International 2010). At Amsterdam Island the decline over the past three generations reaches 74% (CEBC-CNRS unpubl. data).
Population trends are still poorly known due to the remote nature of these islands. Numbers indicate that populations are still declining (TdC and RSPB unpubl. data). At the species’ two breeding locations in the Indian Ocean, Amsterdam (25,000 pairs, 1993) and St. Paul (9,000 pairs, 1993) islands numbers have been declining at an average rate of 3-4% since the early 1970s (CEBC-CNRS unpubl. data). Overall, recent population models indicate that over the past 37 years (three generations) the numbers of Northern Rockhopper Penguins have declined by 57% (Birdlife International 2010).
The Northern Rockhopper Penguin (Eudyptes moseleyi) is found in the temperate South Atlantic and Indian oceans, breeding on seven islands between 37–40° S. Approximately 85% of the global Northern Rockhopper Penguin population is found in the Atlantic Ocean, breeding at the Tristan da Cunha archipelago and Gough Island (Saint Helena, Ascension and Tristan da Cunha UK Overseas Territories). The remaining 15% of the population is found in the Indian Ocean on Amsterdam and St Paul islands (French Southern Territories) (Cuthbert 2013). The location of these islands places the breeding distribution of most Northern Rockhopper Penguins north of the Sub-Tropical Convergence Zone, with the exception of Gough Island, which lies just south to this frontal system. After breeding and moulting, birds depart on their winter migration and spent up to six months at sea before returning to their respective breeding sites the following season (Cuthbert 2013). The foraging ranges of Northern Rockhopper Penguins have been investigated for penguins breeding on Nightingale and Gough islands in the Atlantic Ocean (A. Steinfurth et al. unpubl. data) and for penguins breeding on Amsterdam Island (C.A. Bost, unpubl.data). During the incubation period, penguins forage more than 800 km and 670 km away from their breeding site on Nightingale and Gough Island, respectively, whereas during brooding foraging ranges are restricted to a maximum distance of 35 km (Nightingale Island) and 24 km (Gough Island) (Steinfurth et al. unpubl. data). Tracking data from Nightingale and Gough islands further reveal that birds disperse after moult over an area stretching to the East along the Walvis Ridge and to the region of the Southern African shelf, (approx. 21°S and 15°E), towards the South American continent (approx. 42°W) and South into the region of the Antarctic convergence (approx. 51°S). While Nightingale penguins display high variability in foraging locations during incubation and over-winter migration, penguins breeding on Gough Island show strong directionality with high continuity, travelling South and Southeast. Amsterdam penguins perform looping trips during the incubation, with a mean foraging range of 230 km, but some breeders may forage as far as 410 km off their colony. Brooding birds usually forage much closer to the colony, staying within the region of the shelf (range 8-80 km) (C.A Bost, unpubl.data). After moulting, Amsterdam penguins perform long-range movements of up to 2200 km away from the colony, mainly in longitudinal direction without any return to land. The majority of birds head South-east, along the Indian Ridge and forage south of the southern boundary of the Sub-tropical front using deep waters (3000-3500 m) with very heterogeneous sea surface temperature anomalies and chlorophyll concentrations (Thiebot et al. 2012).
Vagrants have been recorded from South Africa (Rollinson et al. 2013) and the Falkland Islands (Crofts and Robson 2015, Matias et al. 2009). The first breeding attempt of a Northern with a Southern Rockhopper Penguin, Eudyptes chrysocome, was recorded in 2014 on East Falkland (Crofts and Robson 2015).
Adults arrive at the breeding colonies in late July and August. At the Atlantic breeding sites, nests are located in a variety of habitats ranging from open boulder-strewn beaches on Gough Island and Tristan da Cunha to among stands of tussock grass (mainly Spartina arundinacea) on Nightingale, Alex (Middle) and Inaccessible islands (Cuthbert 2013).
In the Indian Ocean, on Amsterdam and St Paul islands, penguins breed in steep or gently sloping ground in a variety of habitats from sea-level up to 170 m above sea-level. Habitats vary from open boulder-strewn beaches to among stands of tussock grass (Spartina arunddinacea and Poa novarae).
Northern Rockhopper Penguins are opportunistic foragers, hunting in different areas during the breeding and non-breeding season. They mainly feed on crustaceans, in particular euphausiids. Other prey items include, fish and cephalopods (Booth and McQuaid 2013, Cuthbert 2013). Juvenile squid co-occurred with crustaceans as the main prey by mass at Amsterdam Island (Tremblay and Cherel 2003). Dietary studies from Tristan da Cunha and Amsterdam Island show seasonal changes in diet with crustaceans and cephalopods, respectively, dominating the diet during the early chick-crèche stage, while fish being the main prey item in the later stages of chick rearing (Tremblay et al. 1997, Booth and McQuaid 2013).
Historically, vast numbers of birds and products from penguins were collected (i.e. eggs were harvested, oil extracted from moulting birds, feathers collected for stuffing pillows and mattresses, and feathers being used for making ornamental table mats on Tristan). These practices have largely ceased by 1955 (Hagen 1952, Wace and Holdgate 1976, Richardson 1984); the egg harvest has been suspended since 2011.
Penguins were also taken as bait for use in crab pots at a number of sites, including at St Paul (Indian Ocean) and Tristan da Cunha (Atlantic Ocean) (Guinard et al. 1998, Cuthbert et al. 2009), and driftnet fishing and rock-lobster fisheries have caused significant mortality in the past (Ryan and Cooper 1991). More recently, however, there is little evidence that fisheries pose a major threat to Northern Rockhopper Penguins (Cuthbert et al. 2009, Cuthbert 2013, Crawford et al. in prep.).
The only reported cases of major predation by invasive species are feral pigs on Tristan and Inaccessible (where pigs were eradicated in 1873 and 1930, respectively). Domestic and feral dogs were also reported to be a problem on Tristan da Cunha (BirdLife International 2010). Although introduced mice Mus musculus and rats Rattus rattus can be found at some of the penguin’s breeding sites, the potential impact is still unknown. Food availability may have been compromised by fisheries, climate change i.e. an increase in sea surface temperature, an increase in fur seal populations, and shifts in marine food webs (Cunningham and Moors 1994, Guinard et al. 1998, Barlow et al. 2002, Hilton et al. 2006, Cuthbert 2013). In March 2011, a cargo ship ran aground on Nightingale Island. The resultant oil spill also reached Inaccessible Island and Tristan da Cunha more than 30km away (http://www.tristandc.com). The long-term effects of the oil spill on the population however are still unknown. The increasing number of ships passing close to the archipelago each year creates a growing risk of chronic oiling as well as further catastrophic spills. Given that the islands are the stronghold for the Northern Rockhopper Penguin, changes in the islands’ population have a substantial impact on the global status of this species.
With only few records of fisheries-related penguin mortality (Ryan and Cooper, 1991, TAAF 2011), and no legal gillnet fishery, penguin bycatch does not appear to be a major threat for the Northern Rockhopper penguin. However, it is suspected that bycatch might be under-reported, particularly if it occurs in illegal fisheries.
On Amsterdam Island, Northern Rockhopper Penguins are exposed to the avian cholera (Pasteurella multocida) but the impact remains unknown (under study).
In 2014, for the first time a breeding attempt between a Northern and a Southern Rockhopper Penguin was recorded in the Falklands Islands. A hybrid chick hatched but died before fledging. The impact of hybridization on the population is unknown.
Conservation Actions Underway
In response to the ever-increasing vulnerability of the fauna and flora, the Tristan community has taken active steps to conserve their islands. Designed to protect the islands’ natural diversity, the Tristan da Cunha Conservation Ordinance of 1976 proclaimed Gough Island and its territorial waters a Wildlife Reserve. The ordinance was further amended in 1997, when Inaccessible Island and its encompassing waters were declared a Nature Reserve. Today, together they form one of only two Natural World Heritage Sites in the UK Overseas Territories. Finally, a Biodiversity Action Plan was adopted and implemented by the Agriculture and Natural Resources Department, which, for the first time on the island, has appointed a Conservation Officer. With the establishment of a Conservation Department including four full-time staff members and the invaluable help and support of the Royal Society for the Protection of Birds, the Joint Nature Conservation Committee, RSSZS and UK Department for International Development, a constant and consistent long-term monitoring of Tristan da Cunha’s key bird populations is finally possible. Historic exploitation of penguins, losses due to their use as rock lobster fishing bait, and mortality from entanglement in drift nets have ceased and been banned, and breeding colonies are protected as nature reserves at all sites in the Tristan group and Gough Island following the Conservation of native Organisms and Natural Habitats (Tristan da Cunha) Ordinance (2006). Regular surveys carried out by the Tristan Conservation Department at Tristan, and more recently at other islands in the group, provide an important and valuable tool to estimate population size and trends. A conservation action on Nightingale Island has recently included erecting a fence to prevent fur seals from encroaching on one of the penguins’ main breeding sites and covering a deep rock crevice that was trapping and killing breeding birds (Cuthbert 2013).
Immediately after the M.S. Oliva spill, as a precautionary measure, the Tristan da Cunha Conservation Department suspended penguin egg collecting. Furthermore, several ecological and demographic studies have been launched in an effort to help understand the potential impact of any natural and/or anthropogenic threats to this population (e.g. Johaadien 2013, Steinfurth et al. unpubl. data). Survival rates are an important driver of population trends; a long-term demographic study will be implemented on Nightingale Island in 2016 to understand the causes of current decline.
An International Species Action Plan and a series of Regional Action Plans were developed in 2008 (BirdLife International 2010), to identify the most important threats to this species and recommend conservation actions, and will be updated in 2017.
Amsterdam and Saint Paul islands are included in the National Nature Reserve of the French Southern and Antarctic Territories (TAAF) created in 2006, comprising the entire surface of these islands as well Crozet, Kerguelen, and a large portion of their surrounding waters. French Southern and Antarctic Territories carry out active environmental policies that are especially linked to the conversation of their biodiversity.
Conservation Actions Proposed
A significant population decrease in recent decades has raised serious concern. To help detect and predict population dynamics there is growing need for baseline data and long-term monitoring datasets play an essential role in the decision-making and sustainable management of species. Continuous demographic long-term monitoring programmes therefore should be considered in the design of future surveys that will further help to assess, understand and reduce any potential impact of natural and/or anthropogenic threats to this population. These include mortality from predators (such as Southern Giant Petrel Macronectes giganteus and Brown Skua Catharacta antarctica lonnbergi) and invasives (such as House Mouse Mus musculus and Black Rat Rattus rattus) and well as anthropogenic impacts such as egg harvesting on Nightingale. Also investigate the impact of disease on this species. Build local capacity and educate residents and tourists to reduce disturbance. Design and implement management plans for the islands where this species occurs, and increase protection of breeding sites. Designate and implement further Marine IBAs.
Identification. Approximately 55 cm in length; red eyes; white underparts and slate-gray upperparts; a straight, bright yellow eyebrow ending in long yellow plumes behind the eye; the top of the head has spiked black feathers. Similar species. Southern Rockhopper Penguin which differ in having a wider supercilium and longer plumes.
Text account compilers
Allinson, T, Mahood, S., Steinfurth, A., Pütz, K., Calvert, R., Ekstrom, J., Shutes, S., Benstead, P., Moreno, R., Stattersfield, A., McClellan, R.
Hilton, G., Steinfurth, A., Bond, A., Barbraud, C., Bost, C., Cuthbert, R.
BirdLife International (2018) Species factsheet: Eudyptes moseleyi. Downloaded from http://www.birdlife.org on 16/07/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/07/2018.