From the paper: Fig 2. The relationship between wing loading (N m−2) and aspect ratio (dimensionless) for flying birds

Lesley Thorne (School of Marine and Atmospheric Sciences, Stony Brook University, USA) and colleagues have published a review and synthesis on the impact of wind on seabirds in the journal Marine Ecology Progress Series.

The paper’s abstract follows: “For decades, studies have highlighted links between wind patterns and the behavior, ecology, distribution, energetics and life history of seabirds. However, only relatively recently have advancements in tracking technologies and improvements in the resolution of globally-available wind data allowed wind impacts on seabirds to be quantified across multiple spatiotemporal scales. Here, we review and synthesize current knowledge of the effects of wind on seabirds. We first describe global patterns of wind circulation and relevant atmospheric processes and discuss the relationship between seabird morphology, flight performance and behavior relative to wind. We then develop a conceptual model linking seabird movement strategies to wind, morphology, flight capabilities and central-place constraint. Finally, we examine how wind influences seabird populations via effects on flight efficiency and energetics, and wind impacts associated with climate variability and severe weather. We conclude by highlighting research priorities for advancing our understanding of the effects of wind on seabird ecology and behavior; these include assessing how and to what extent seabirds use ocean waves for efficient flight, understanding how seabirds sense and anticipate wind patterns, and examining how wind has shaped seabird evolution. Future research should also focus on assessing how wind modulates habitat accessibility, and how this knowledge could be incorporated into theory of seabird habitat use. Moreover, approaches that focus on mechanistic links between climate, wind and demography are needed to assess population-level effects, and will be imperative to understanding how seabirds may be impacted by climate-driven changes to wind patterns.“

Reference: 

Thorne LH, Clay TA, Phillips RA, Silvers LG, Wakefield ED (2023) Effects of wind on the movement, behavior, energetics, and life history of seabirds. Mar Ecol Prog Ser 723:73-117. https://doi.org/10.3354/meps14417

11 December 2023

Getting him up on his toes.  Wisdom (left, with her colour band on show) engages in a mutual display with a metal-banded bird, photograph by Jon Plissner, USFWS, 03 December 2023

Wisdom, a female Laysan Albatross Phoebastria immutabilis, who is the world’s oldest known wild bird, recently returned to the Midway Atoll National Wildlife Refuge.  She was first spotted for the 2023/24 breeding season on 1 December this year by US Fish and Wildlife Service Volunteer Nick Minnich, being identified by her red colour band Z3333.  Her last partner, named Akeakamai, has not been seen this and in the two previous seasons and is likely no longer alive.

“Jonathan Plissner, supervisory wildlife biologist at the national wildlife refuge, said he doesn’t expect Wisdom to nest this year, but he did witness the possibly 72-year-old seabird participating in mating dances.  Biologists [the late Chandler Robbins] first identified and banded Wisdom in 1956 after she laid an egg, and the large seabirds aren’t known to breed before age five.  It is estimated that Wisdom has produced 50-60 eggs and as many as 30 chicks that fledged.”

Because it is late in the year Wisdom will likely not lay an egg in the current breeding season.

A third bird joins in, photograph by Jon Plissner, USFWS, 03 December 2023

Information from the Facebooks groups of Friends of the Midway Atoll National Wildlife Refuge and Pacific Islands: U.S. Fish and Wildlife Service.

Read more about Wisdom in previous posts to ACAP Latest News from here.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 07 December 2023

 This Grey-headed Albatross survived a crash landing in a lava field.  Not all are so lucky, photograph by Janine Schoombie

Janine Schoombie (Department of Mechanical and Aeronautical Engineering, University of Pretoria, South Africa) and colleagues have published in the journal Marine Ecology Progress Series on mortality in Grey-headed Albatrosses Thalassarche chrysostoma crash landing in strong winds below their inland colony.

A Grey-headed Albatross flies over a lava field on Marion Island, photograph by Kim Stevens

The paper’s abstract follows:

“Albatrosses exploit winds to travel vast distances across the ocean. Their morphology is adapted for low-cost dynamic soaring flight, but these adaptations confer low manoeuvrability, which may be risky when flying over land. This study investigates how wind conditions influence Endangered grey-headed albatross Thalassarche chrysostoma crashes in the valley below an inland sub-colony on Marion Island. Carcass surveys were conducted in a 1 km² area spanning the length of this sub-colony (ca. 4000 breeding pairs) from October 2017 to June 2021. Hundreds of adult and fledgling albatross carcasses were discovered, some with evidence of fatal crash-landings in the form of broken bones. Wind data measured on the cliff-top above the colony were hsupplemented by computational fluid dynamics simulations of wind vectors over Marion Island. Most crashes occurred below the centre of the colony, where there are strong gradients in wind speed and direction under the dominant westerly wind conditions. Observations of albatrosses in flight indicate that most birds are killed when attempting to leave the colony, specifically when flying low above ground in strong wind. An average of at least 41 adults and 40 fledglings died after crashing into the valley annually. This represents an estimated 2% of the annual production of fledglings, 0.5% of the estimated annual breeding adult population and 11% of the adult annual mortality, suggesting a substantial cost to breeding at this inland site. For these long-lived seabirds, even low levels of adult mortality can have potential demographic consequences. This is the first study to document persistent wind-driven, land-based mortalities in albatrosses.”

Reference:

Schoombie, J., Schoombie, S., Connan, M., Jones, C.W., Risi, M., Craig, K.J., Smith^, L., P. G. Ryan, P.G. & Shepard, E.L.C. 2023.  Impact of wind on crash-landing mortality in grey-headed albatrosses Thalassarche chrysostoma breeding on Marion Island.  Marine Ecology Progress Series 723: 213-225.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 05 December 2023

Wandering Albatrosses such as the one pictured, are known to forage in Antarctic waters; photograph by Kirk Zufelt

Today is Antarctica Day, a commemorative day underscoring the significance of the Antarctic Treaty as one of the most successful international agreements in history. The Treaty, which designates Antarctica as a scientific preserve devoted exclusively to peaceful purposes, has been instrumental in fostering an environment that has led to numerous breakthroughs in our understanding of Earth and its ecosystems. There are now 56 Parties to the Treaty which includes all 13 Parties to The Albatross and Petrel Agreement.

Over the past six decades, the Antarctic Treaty has emerged as a symbol of unity and shared commitment to the peaceful exploration of the southernmost continent. By promoting international scientific collaboration, the Treaty has paved the way for an abundance of research initiatives that have contributed to our collective knowledge of climate change, biodiversity, and glaciology. 

The ongoing dedication to the Treaty's core pillars will be essential in safeguarding Antarctica's unique environment and ensuring that it continues to be a beacon of international cooperation for generations to come. 

01 December 2023