Pages

Friday, February 24, 2017

The oldest fossilized giant penguin

Penguins diversified earlier than previously assumed
Date:
February 23, 2017
Source:
Senckenberg Research Institute and Natural History Museum
Summary:
A recently discovered fossil of a giant penguin with a body length of around 150 centimeters has been described in a new article. The new find dates back to the Paleocene era and, with an age of approximately 61 million years, counts among the oldest penguin fossils in the world. The bones differ significantly from those of other discoveries of the same age and indicate that the diversity of Paleocene penguins was higher than previously assumed. The team of scientists, therefore postulates that the evolution of penguins started much earlier than previously thought, probably already during the age of dinosaurs.

The foot bones of the new giant penguin (left), compared to those of an Emperor Penguin, the largest living penguin species (right).
Credit: © Senckenberg
 
Together with colleagues from New Zealand, Senckenberg scientist Dr. Gerald Mayr described a recently discovered fossil of a giant penguin with a body length of around 150 centimeters. The new find dates back to the Paleocene era and, with an age of approx. 61 million years, counts among the oldest penguin fossils in the world. The bones differ significantly from those of other discoveries of the same age and indicate that the diversity of Paleocene penguins was higher than previously assumed. In their study, published in the Springer scientific journal The Science of Nature, the team of scientists, therefore postulates that the evolution of penguins started much earlier than previously thought, probably already during the age of dinosaurs.

The fossil sites along the Waipara River in New Zealand's Canterbury region are well known for their avian fossils, which were embedded in marine sand a mere 4 million years after the dinosaurs became extinct. "Among the finds from these sites, the skeletons of Waimanu, the oldest known penguin to date, are of particular importance," explains Dr. Gerald Mayr of the Senckenberg Research Institute in Frankfurt.

Together with colleagues from the Canterbury Museum in New Zealand, Mayr now described a newly discovered penguin fossil from the famous fossil site. "What sets this fossil apart are the obvious differences compared to the previously known penguin remains from this period of geological history," explains the ornithologist from Frankfurt, and he continues, "The leg bones we examined show that during its lifetime, the newly described penguin was significantly larger than its already described relatives. Moreover, it belongs to a species that is more closely related to penguins from later time periods."

According to the researchers, the newly described penguin lived about 61 million years ago and reached a body length of approx. 150 centimeters -- making it almost as big as Anthropornis nordenskjoeldi, the largest known fossil penguin, which lived in Antarctica around 45 to 33 million years ago, thus being much younger in geological terms. "This shows that penguins reached an enormous size quite early in their evolutionary history, around 60 million years ago," adds Mayr.

In addition, the team of scientists from New Zealand and Germany assumes that the newly discovered penguin species also differed from their more primitive relatives in the genus Waimanu in their mode of locomotion: The large penguins presumably already moved with the upright, waddling gait characteristic for today's penguins.

"The discoveries show that penguin diversity in the early Paleocene was clearly higher than we previously assumed," says Mayr, and he adds, "In turn, this diversity indicates that the first representatives of penguins already arose during the age of dinosaurs, more than 65 million years ago."

Story Source:
Materials provided by Senckenberg Research Institute and Natural History Museum. Note: Content may be edited for style and length.

Journal Reference:
  1. Gerald Mayr, Vanesa L. De Pietri, R. Paul Scofield. A new fossil from the mid-Paleocene of New Zealand reveals an unexpected diversity of world’s oldest penguins. The Science of Nature, 2017; 104 (3-4) DOI: 10.1007/s00114-017-1441-0


Senckenberg Research Institute and Natural History Museum. "The oldest fossilized giant penguin: Penguins diversified earlier than previously assumed." ScienceDaily. ScienceDaily, 23 February 2017. <www.sciencedaily.com/releases/2017/02/170223102022.htm>.

Tuesday, February 21, 2017

Penguin fossil calls Waikato Museum home

A 28 million-year-old penguin fossil has officially become part of the museum's permanent collection.
CHRISTINE CORNEGE FAIRFAX NZ
 
A 28 million-year-old penguin fossil has officially become part of the museum's permanent collection.
It's 28 million years old, weighed as much as Stephen Donald, and was the about the same height as Prince.
And it calls the Waikato Museum home.
A local penguin fossil, found by Hamilton Junior Naturalist Club in 2006 has officially become part of the museum's permanent collection.

The Kawhia giant penguin was discovered by a group of young explorers from the Hamilton Junior Naturalist Club in 2007.
CHRISTINE CORNEGE FAIRFAX NZ
 
The Kawhia giant penguin was discovered by a group of young explorers from the Hamilton Junior Naturalist Club in 2007.
The bones, preserved in Mudstone, have pride of place in a glass cabinet near the entrance. The bones were found in Kawhia.
Although the fossil has been at the museum for the past several years there was a process to get it officially part of the museum's permanent collection.

A painting of the Kawhia giant penguin by Ronald Cometti.
Simon Cometti and Amanda Wilson
A painting of the Kawhia giant penguin by Ronald Cometti.

And it appears to be a hit with most of the visitors.
Sydney man John Toohey was fascinated by the fossil during his visit.
"It's good for a fossil to see other fossils," he joked.
The penguin - which scientists believed weighed about 100kg, and was 1.5m tall- was comparatively a lot larger than modern day penguins.
An Emperor penguin weighs 30kg and was 1.15m tall - both lighter and shorter than it's ancient ancestor.
"I really like seeing how things develop and the synergies of other forms of life, the science of continuity and how things have developed over time," Toohey said.
Though the fossil did not fare as well under his partner's gaze.
"There's only so much information I can hold in my brain at a time, and fossils don't fit," Robyn Alexander said.
"I'm just going to have to say sorry to my granddaughter because I can't tell her about the penguin fossil when I get home."
But Alexander did sing the praises of another famous New Zealand penguin - Dunedin's Yellow Eyed Penguin.
She saw a cluster of the birds huddling together, the eyes were the most amazing things she had ever seen, Alexander said.
"Now that sort of penguin I have space for in my brain."

source

Friday, February 17, 2017

New guidance on hand-rearing decisions for endangered penguin chicks


Penguin chicks Southern African Foundation for the Conservation of Coastal Birds
 

Penguin chick being checked over Southern African Foundation for the Conservation of Coastal Birds

Press release issued: 17 February 2017
The first model of its kind which provides guidance on the survival likelihood of abandoned penguin chicks admitted to rehabilitation has been developed by researchers from the Universities of Bristol, Exeter, Cape Town, the Southern African Foundation for the Conservation of Coastal Birds (SANCCOB) and Bristol Zoological Society.
Globally the use of rehabilitation for conservation is growing, with many research papers monitoring the success of individuals post-release. Rearing chicks that are unlikely to survive naturally has the potential to significantly contribute to the conservation of threatened bird species, such as the African penguin.

Annually, abandoned African penguin chicks are hand-reared by SANCCOB and released back into the wild. The chicks are abandoned if the adults start to moult before the chick fledges.
Once an adult begins to moult it is no longer waterproof, so can no longer feed its chick. A scarcity of prey leads to slow growth rates and can cause chicks not to fledge in time. Abandoned chicks would not survive without intervention.

This 'chick bolstering project' is an important conservation action for these endangered birds. It aims to bolster the African penguin population while methods to establish new colonies near high prey abundance are developed.

Decisions of whether and when to remove animals from the wild rarely use quantitative criteria. Where such criteria are assessed, there have been few studies to investigate their efficacy to predict rehabilitation outcomes.

In this new study, published today in Animal Conservation, researchers investigate whether a body condition index (mass correcting for structural size), other structural measurements and sex can predict rehabilitation outcome.

Joanne Morten from the University of Bristol's School of Biological Sciences, was lead author of the research.

She said: "Using data from over 1,400 chicks rescued over six breeding seasons, we identified clear body condition thresholds that colony managers can use to prioritise the removal of chicks.
"These thresholds also allow the rehabilitators to rapidly identify individuals in need of critical attention."

African penguin colony managers are currently using the body condition index to guide removal. This study demonstrates its effectiveness, with only 2.3 percent of chicks admitted with a body condition index so low there was a less than 50 percent chance of survival.

Joanne added: "However, almost a third of chicks admitted may well have survived naturally. Hand-reared African penguin chicks are just as successful as their naturally-reared counterparts, but we don’t want to cause undue stress and use resources unnecessarily. The body condition thresholds identified in this study can be used to guide future management strategies, and can be rapidly incorporated.

"The body condition index uses mass and bill length, two measurements that are easy and quick, minimising handling stress.

"This is an extremely useful guide which, when used in conjunction with nest monitoring, can effectively identify chicks that have been abandoned. This tool could be useful, not just to the endangered African penguin, but other species where chicks can be successfully hand-reared."

Further information

Paper:
‘Body condition as a quantitative tool to guide hand-rearing decisions in an endangered seabird’ by J.M. Morten, N.J. Parsons, C. Schwitzer, M.W. Holderied and R.B. Sherley in Animal Conservation.

source

Thursday, February 16, 2017

New study reveals what penguins eat

February 15, 2017
New study reveals what penguins eat
Gentoo penguin chicks at Bird Island. Credit: British Antarctic Survey
The longest and most comprehensive study to date of what penguins eat is published this month. The study, published in the journal Marine Biology, examines the diets of gentoo penguins (Pygoscelis papua) at Bird Island, South Georgia over a 22 year period and is part of a project investigating the Southern Ocean ecosystem and its response to change.
Penguin parents forage at sea returning to feed their chicks every day. The team, based at British Antarctic Survey (BAS), found that between 1989 and 2010 gentoo penguins ate approximately equal amounts of crustaceans, (mainly Antarctic , a small shrimp-like creature) and fish.

Twenty-six different prey species were found in the diet, including squid, octopus and 17 species of fish. The composition of gentoo penguin diets was variable from year to year, with krill the dominant food in 10 years of the study and fish in 12 years. Successful breeding (the number of chicks fledged per nest per year) was strongly related to the amount of krill in the diet, with few chicks fledging in years where krill was particularly scarce.

The team then compared the diets of gentoo penguins with those of (Eudyptes chrysolphus) also resident at Bird Island. Both species are able to switch to other prey when krill availability is low. However, where gentoo penguins have a broad and variable diet, macaroni penguins are specialist predators on krill. Their differing diets and foraging ranges allow the two penguin species to successfully coexist at Bird Island, South Georgia.
New study reveals what penguins eat
The team at BAS studied gentoo colonies on Bird Island over a 22 year period. Credit: British Antarctic Survey
Lead author, Dr Claire Waluda, penguin ecologist at BAS says:
"Gentoo and macaroni penguins are important indicator species and monitoring changes in their diets can help us understand changes in the Southern Ocean ecosystem."

"This work highlights the importance of long-term data collection and supports the work of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), which is responsible for setting catch limits for commercial krill and fish in the Southern Ocean. Their aim is to protect marine ecosystems and maintain sustainable levels of fishing in this region."

The paper summarises one of the longest time series of penguin diet currently available globally. Long-term variability in the diet and reproductive performance of at Bird Island, South Georgia by Claire M. Waluda, Simeon L. Hill, Helen J. Peat and Philip N. Trathan is published this month in the journal Marine Biology.

 
 
More information: Claire M. Waluda et al. Long-term variability in the diet and reproductive performance of penguins at Bird Island, South Georgia, Marine Biology (2017). DOI: 10.1007/s00227-016-3067-8

source