A Galapagos Petrel in its burrow, photograph by Carolina Proaño

Welcome news comes from an island in the Galapagos Islands where early signs following a recent eradication operation look promising, especially after the failures on Gough Island in the South Atlantic and Midway Atoll in the North Pacific, where House Mice Mus musculus are sadly still present after eradication operations carried out over the last three years.

The Galapagos Conservation Trust reports on the Floreana Ecological Restoration Project: “Last October, the restoration of Floreana Island reached an exciting milestone, as the eradication of invasive [Black Rats Rattus rattus and House Mice], over a decade in the planning, finally began.  The project, led by the Galapagos National Park and the Galapagos Biosecurity Agency in partnership with the Floreana community, co-executed by Fundación Jocotoco and Island Conservation, and supported by Galapagos Conservation Trust, Durrell Wildlife Conservation Trust and others, has as its ultimate aim the reintroduction of 12 locally extinct species and the restoration of the island’s degraded ecosystem.  The removal of invasive species is key to the project’s success, and initial indications regarding the eradication of rats and mice, which concluded in December 2023, are positive.”

Successful eradication of Floreana’s introduced rodents should be a help to the island’s breeding population of Critically Endangered Galapagos Petrels Pterodroma phaeopygia, which are endemic to the Galapagos Islands.  Floreana supports over 60% of the species’ global population. One study found almost half the Galapagos Petrel nests on Floreana were preyed upon by feral cats Felis catus (and likely also by Black Rats) despite local control efforts.  However, no public announcement has yet been made on the outcome of the planned effort to eradicate the cats with meat-based “sausages” containing Para-aminopropiophenone (PAPP) at the same time as the rats and mice (click here).

A view of Floreana Island, photograph from Island Conservation

With the eradication attempt showing promising signs for at least the two rodents (although a final announcement of success usually waits for two years with no signs of them) a decision was made to release the endemic Galapagos finches which had been kept in temporary captivity in aviaries on the island during the baiting operation.  A total of 510 finches of five species was released in batches over January and February this year into their natural habitats on the island as part of the Floreana Ecological Restoration Project.  Some of the first released birds were radio tracked to assess if it was safe to release all the birds (click here).

Floriana is an inhabited island with a human population of 160.  If the rats and mice (and also the cats) have definitely gone, it will join with Australia’s inhabited Lord Howe Island, now free of its rats and mice, as yet another success for what must surely be one of the world’s most important conservation activities: ridding islands of their introduced predators.

With grateful thanks to Kelly Hague, Senior Philanthropy Manager and and Tom O’Hara, Communications Manager, Galapagos Conservation Trust.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 02 April 2024

From the paper: Figure 1. Hawai‘i Pacific University students weigh ‘Ua‘u kani chicks to study phenology, chick growth, and reproductive success.

David Hyrenbach (Hawai‘i Pacific University) and Alyssa Piauwasdy (Hawai‘i Pacific University & Oikonos Ecosystem Knowledge) study Wedge-tailed Shearwaters or 'Ua'u kani Ardenna pacifica; Least Concern) in the Freeman Seabird Preserve on the Hawaiian island of Oahu. They write of the most recent breeding season in the Hawaii Audubon Society journal ‘Elepaio’:

"2023 Update

With participation of over 20 volunteers, we counted the number of Wedge-tailed Shearwaters (Ardenna pacifica) nesting at the Freeman Seabird Preserve during the incubation (July 14) and early chick-rearing (September 14) periods. In July, we documented 427 active nests, which is the highest count to date and surpasses the previous peak of 423 nests observed in 2022 (Hyrenbach & Piauwasdy 2023). Overall, the annual population counts continue to show a statistically significant trend (F = 395.939; df = 1, 13; p <0.001), with an average increase of 24.7 (+/- 4.8 S.D.) nests per year, which captures 97 % of the variability in the 15-year time series (2009 - 2023; Fig. 2). This trend suggests that the colony continues to grow, in part due to the collaborative restoration efforts.

A Wedge-tailed Shearwater; photograph courtesy of Pacific Rim Conservation

 Ongoing Efforts

The 2024 winter marks the second year of a tracking and tag effects study to determine where in the big Pacific Ocean the ‘ua‘u kani migrate and spend winter, after leaving FSP in late November. In August 2022, we tagged 25 adults with a geolocator (GLS) tag mounted on a USFWS metal band. In April 2023, we retrieved 24 out of 25 tags (96% recovery rate), gathering over 5,700 days of data that revealed their at- sea movements. We tagged an additional 30 adults in August 2023 to learn about ‘ua‘u kani post-breeding movements during the El Niño. We will retrieve these GLS tags starting in April 2024, along with the one remaining GLS from the 2022-23 winter.

Research

Starting in April 2024, we will check returning adult shearwaters to retrieve the GLS tags and to resight the tagged and control birds. With the second year of tracking underway, we are currently analyzing the 2022-23 winter data and developing statistical models to understand the oceanographic drivers of shearwater winter habitat. By comparing shearwater movements during the past La Niña (2022-23) and the current El Niño (2023-24), we seek to understand how changing oceanographic conditions influence the timing of their migration and their over- wintering destinations. Population censusing and nest monitoring for phenology, chick growth, and reproductive success will continue in 2024, to augment our 15-year time series."

Read more on the 2023 breeding season here.

Reference:

Hyrenbach, K.D. & Piauwasdy, A. 2023.  Shearwater nesting at Freeman Seabird Preserve: ‘Ua‘u kani cope with El Niño conditions. ‘Elepaio’ 84(2): 12-14.

01 April 2024

Figure 1 from the paper shows examples of wildlife detected in satellite and unmanned aircraft system (UAS) imagery. (a) VHR satellites can be used to count individual animals provided that they meet key detection criteria: in an open habitat, of suitable size, and of contrasting colour to the background. For instance, African elephants are visible in open savannahs using 31 cm resolution WorldView-3 imagery [14]. (b) Indirect counts can be performed for species which are not directly detectable; for example, colony sizes of emperor penguins can be estimated from the colony area or the extent of guano staining using 10 m resolution Sentinel-2 satellite imagery [15]. (c) Spectral imagery collected by UAS is typically of higher resolution than that of satellite sensors, enabling counts of smaller animals, such as black-browed albatrosses, in open habitats [16]. (d) For species in closed-cover habitats, for instance, koalas in tree canopy (shown in yellow box), thermal cameras mounted on UAS can aid detection [17]. All panels are cropped versions of the originals and are reproduced under CC BY 4.0 licenses.

Marie R. G. Attard (British Antarctic Survey, Natural Environment Research Council, Cambridge, UK) and colleagues have published open access in the journal, Remote Sensing, Census Guidelines using drones or satellites. 

The paper, which was discussed at the 7^th Meeting of the Albatross and Petrel Agreement’s Population and Conservation Status Working Group, provides an introduction for wildlife biologists and managers relatively new to the field on how to implement remote-sensing techniques (satellite and unoccupied aircraft systems) for counting large vertebrates on land, including marine predators that return to land to breed, haul out or roost, to encourage wider application of these technological solutions.

A link to the article is also available on the ACAP website via the Conservation Guidelines page. 

The abstract follows:

“Although many medium-to-large terrestrial vertebrates are still counted by ground or aerial surveys, remote-sensing technologies and image analysis have developed rapidly in recent decades, offering improved accuracy and repeatability, lower costs, speed, expanded spatial coverage and increased potential for public involvement. This review provides an introduction for wildlife biologists and managers relatively new to the field on how to implement remote-sensing techniques (satellite and unoccupied aircraft systems) for counting large vertebrates on land, including marine predators that return to land to breed, haul out or roost, to encourage wider application of these technological solutions. We outline the entire process, including the selection of the most appropriate technology, indicative costs, procedures for image acquisition and processing, observer training and annotation, automation, and citizen science campaigns. The review considers both the potential and the challenges associated with different approaches to remote surveys of vertebrates and outlines promising avenues for future research and method development.”

Reference:

Attard, M.R.G., Phillips, R.A., Bowler, E., Clarke, P.J., Cubaynes, H., Johnston, D.W., Fretwell, P.T. 2024. Review of Satellite Remote Sensing and Unoccupied Aircraft Systems for Counting Wildlife on Land. Remote Sensing https://doi.org/10.3390/rs16040627

28 March 2024

2A Northern Royal Albatross chick in ICU after eating plastic, photograph by the Wildlife Hospital

A 10-day old Endangered Northern Royal Albatross Diomedea sanfordi chick has died while under care in the Wildlife Hospital in Dunedin after it swallowed soft plastic that had been regurgitated to it by its parent at Taiaroa Head/Pukekura, South Island, New Zealand.  The soft but tough plastic was discovered during necropsy to have caused an obstruction in the gastrointestinal tract, which ultimately led to starvation and organ failure.

Plastic (and squid beaks) found in the regurgitation of an albatross chick, photograph by the Department of Conservation

Department of Conservation biodiversity ranger Sharyn Broni said it was the first death of its kind at the Taiaroa Head colony, but rangers had feared something like this could happen after other close calls in recent years.

“This heartbreaking incident is a reminder it's vital to dispose of plastic rubbish carefully.  People can also help by picking up litter they see on beaches, near waterways, or out on the ocean. Every piece you pick up could save a seabird's life.”

“My Little Pony”, photograph by Theo Thompson

In May 2021, a 9-cm-long plastic pony toy, which had been regurgitated by a parent, was found in a chick's nest.  Fortunately, in that case the chick did not swallow it, Broni said.

"DOC staff found plastic in almost all the [albatross] chick regurgitations checked last season.  The most common plastics seen were bottlecaps, however items like a plastic syringe were also found.”

Read more on the hatchling's death.  Previous plastic items in addition to the pony toy found associated with Taiaroa Head’s albatrosses have included bottle caps, squid lures, fishing floats, a container tab and the handle of an infant formula scoop.

Plastic pollution was the theme for last year’s World Albatross Day (WAD2023) on 19 June.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 28 March 2024