Rachel Buxton (Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, USA) and colleagues have published a review paper in the journal Biodiversity and Conservation on deciding whether active or passive management should follow alien eradications on seabird islands.

The paper’s abstract follows:

“Following the removal of an introduced species, island restoration can follow two general approaches: passive, where no further intervention occurs and the island is assumed to recover naturally, and; active, where recovery of key taxa (e.g. seabirds) is enhanced by manipulating movement and demography. Steps for deciding between these techniques are: (1) outlining an explicit restoration goal; (2) building a conceptual model of the system; (3) identifying the most effective management approach; and (4) implementing and monitoring outcomes.

After decades of island restoration initiatives, retrospective analysis of species' responses to active and passive management approaches is now feasible.

We summarize the advantages of incorporating these analyses of past restoration results as an initial step in the decision-making process.  We illustrate this process using lessons learned from the restoration of seabird-driven island ecosystems after introduced vertebrate eradication in New Zealand.  Throughout seven decades of successful vertebrate eradication projects, the goals of island restoration have shifted from passive to active enhancement of island communities, which are heavily dependent on burrow-nesting petrel population recovery.  Using a comparative analysis of petrel response to past predator eradications we built a conceptual model of petrel recovery dynamics and defined key site and species characteristics for use in a stepwise decision tree to select between active or passive seabird population management.

Active restoration techniques should be implemented when seabird populations are absent or declining; and on islands with no nearby source colony, small remnant colonies, highly altered habitat with shallow soil and slopes, and with competitive species pairs.  As we continue to restore complex island communities, decision-making tools using a logical, step-wise framework informed by previous restoration successes and failures can aid in increasing understanding of ecosystem response.

Sooty Shearwater, photograph by the West Coast Penguin Trust

With thanks to Barry Baker.

Reference:

Buxton, R.T., Jones, C.J., Lyver, P.O'B., Towns, D.R. & Borrelle, S.B. 2016.  Deciding when to lend a helping hand: a decision-making framework for seabird island restoration.  Biodiversity and Conservation 25: 467-484.

John Cooper, ACAP Information Officer, 18 March 2016

An Arctic or Northern Fulmar Fulmarus glacialis was photographed in New Zealand waters in the general vicinity of the Snares Islands on 9 February 2014 by fisheries observer Leon Berard (click here).

NOTE: file photo of an Arctic Fulmar, not of the New Zealand record

This exceptional record, likely to be the first ever for the Southern Hemisphere (there appear to be none for both Australian and southern African waters) has this month been accepted by the Birds New Zealand Records Appraisal Committee.

The bird was identified by differences in bill colouration from the more-expected Antarctic Fulmar F. glacialoides and that it was a dark-phase individual – not seen in the Antarctic species.  It has been suggested that the relatively small head and slim bill of the New Zealand bird indicates that it came from the North Pacific population rather than from the North Atlantic.

Click here for the new entry for Arctic Fulmar on New Zealand Birds Online.

With thanks to Colin Miskelly.

John Cooper, ACAP Information Officer, 17 March 2016

Victoria González Carman (Instituto de Investigaciones Marinas y Costeras, Universidad Nacional de Mar del Plata, Argentina) and colleagues have published in the ICES Journal of Marine Science on the roles of albatrosses, seals and turtles in identifying key ecological areas, such as highly productive Río de la Plata region which sustains the main coastal fisheries of Uruguay and Argentina.

The paper’s abstract follows:

“During the last centuries, populations of marine megafauna—such as seabirds, turtles, and mammals—were intensively exploited.  At present, other threats such as bycatch and pollution affect these species, which play key ecological roles in marine ecosystems as apex consumers and/or nutrient transporters.  This study analyses the distribution of six megafaunal species (Chelonia mydas, Caretta caretta, Dermochelys coriacea, Thalassarche melanophris, Otaria flavescens, and Arctocephalus australis) coexisting in the Southwestern Atlantic to discuss their protection in terms of current management strategies in the region.  Through the prediction of the species potential distributions and their relation to bathymetry, sea temperature and oceanographic fronts, key ecological areas are defined from a multi-taxa perspective.  Information on the distribution of 70 individuals (18 sea turtles, 19 albatrosses, and 33 otariids) was obtained through satellite tracking conducted during 2007–2013 and analysed using a Geographic Information System and maximum entropy models.  During the autumn–winter period, megafaunal species were distributed over the continental shelves of Argentina, Uruguay, and Brazil, mainly over the Argentine Exclusive Economic Zone and the Argentina-Uruguay Common Fishing Zone.  Despite some differences, all megafaunal species seems to have similar environmental requirements during the autumn–winter period.  Mostly waters shallower than 50 m were identified as key ecological areas, with the Río de la Plata as the habitat with the highest suitability for all the species.  This area is highly productive and sustains the main coastal fisheries of Uruguay and Argentina, yet its role as a key ecological area for megafaunal species has been underestimated until now.  This approach provides a basis to analyse the effect of anthropic activities on megafaunal species through risk maps and, ultimately, to generate knowledge to improve national and bi-national management plans between Argentina and Uruguay.”

Black-browed Albatross, photograph by Juan Pablo Seco Pon

With thanks to Juan Pablo Seco Pon.

Reference:

González Carman, V., Mandiola, A., Alemany, D., Dassis, M., Seco Pon, J.P., Prosdocimi, L., Ponce de León, A., Mianzan, H., Acha, E.M., Rodríguez, D., Favero, M. & Copello, S. 2016.  Distribution of megafaunal species in the Southwestern Atlantic: key ecological areas and opportunities for marine conservation.  ICES Journal of Marine Science.  doi:10.1093/icesjms/fsw019.

John Cooper, ACAP Information Officer, 16 March 2016.

The following text come from the Hutton's Shearwater Charitable Trust of Kaikoura, New Zealand.

“The nationally endangered Hutton's shearwater (Puffinus huttoni) is the only seabird globally to breed in a sub-alpine environment, with the only two breeding colonies remaining in the Seaward Kaikoura Range in the South Island.

From an estimated population numbering millions of birds, introduced mammals and changes in land use have decreased the Hutton’s shearwater population to less than half a million. There is an estimated breeding population of more than 100,000 pairs, with a similar number of non-breeding birds visiting colonies early in the breeding season. Despite this relatively high number the species is regarded as nationally endangered because of past declines (evident from extinct colonies) and the threats still faced.

The Hutton's shearwater was long known to Māori, providing a major sustainable source of protein to Ngāti Kuri. Chicks were harvested from their burrows shortly before fledging and preserved in pōhā/kelp bags. The Hutton’s shearwater was first officially described in 1912, and later there were anecdotal reports from high country farmers, hunters and various others of 'muttonbird' burrows at high elevations in the Seaward Kaikoura Range, behind Kaikoura. In 1965, following on from these leads, Geoff Harrow found carcasses in the headwaters of the Kowhai River at altitudes between 1,200 and 1,800 m above sea level, that were confirmed as Hutton's shearwaters.

Extensive searching led to the confirmation of eight colonies, but only two remnant colonies remain today. At least ten colonies formerly existed in both the Seaward Kaikoura and Inland Kaikoura Ranges; there is questionable evidence that the species may have bred beyond these mountains.

Habitat loss and predation by introduced mammals is the main threat to remaining Hutton’s shearwater populations. Feral pigs are considered a major threat, being responsible for the loss of colonies in the last 100 years. Deer and chamois are known to trample nesting burrows, while stoats and cats will eat young birds and eggs. Both of the remaining breeding colonies are confined to a small area, making the birds extremely vulnerable to events such as landslides or predation which could lead to extinction.

A third colony (Te Rae o Atiu) was established on the Kaikoura Peninsula in 2005, to ensure long-term survival. This was a joint project by Te Runanga o Kaikoura, Whale Watch Kaikoura, Department of Conservation, and Forest & Bird, with support from the local community. A predator-proof fence was then constructed by the Hutton’s Shearwater Charitable Trust in 2010. Multiple translocations occurred, with chicks transferred from mountain burrows to artificial burrows at the new colony. Volunteers hand fed chicks for a 2-3 week period, until they fledged. During this time the chicks ‘imprinted’ on the site, ensuring they would return to the new colony to breed. Chicks raised there are already returning and producing their own offspring.”

Read earlier accounts of Hutton’s Shearwaters in ACAP Latest News and visit the trust’s Facebook page.

Hutton's Shearwater at sea

John Cooper, ACAP Information Officer, 15 March 2016