Songbirds singing and dancing, new study


This November 2015 video says about itself:

Hidden Bird “Tap-Dancing” Behavior Revealed in Slow-Motion​ Footage | National Geographic

High-speed footage reveals a unique courtship behavior of the blue-capped cordon bleu that has never been observed before in birds.

From Hokkaido University in Japan:

Couples showing off: Songbirds are more passionate in front of an audience

October 3, 2018

Both sexes of a songbird called the blue-capped cordon-bleu intensify courtship performances that involve singing and dancing in the presence of an audience, especially if it is a member of the opposite sex, an international team of researchers has discovered.

Mutual courtship displays have generally been understood as a form of private communication between a male and a female, and many researchers have focused on this aspect. The cordon-bleu is a socially monogamous songbird found in Africa. In its courtship display, both sexes sing and sometimes add a unique dance that resembles tap dancing.

Birds that live in flocks like cordon-bleus are thought to carry out courtship communications in the presence of other birds. However, very little research has been conducted on whether the individuals performing courtship displays are influenced by the presence of other birds. In the present study published in Science Advances, researchers from Hokkaido University in Japan and the Max Planck Institute for Ornithology in Seewiesen, Germany, focused on this so-called audience effect.

In the experiment, the researchers placed paired couples in situations with and without an audience and observed their behavior.

The researchers found that cordon-bleu couples tended to sing more courtship songs accompanied by dancing when an audience — especially if it is a member of the opposite sex — is present. In contrast, courtship displays without dancing were suppressed. As the birds were directing their courtship dancing toward their partners rather than the audience, Nao Ota of the research team concludes: “Performing a more elaborate courtship display toward a partner likely is meant to advertise the relationship to other individuals, which is a significant act among birds who live in flocks.” Researchers hypothesize that loyalty and bonding are necessary for cordon-bleu pairs to maintain long-term coupling relationships.

“This could provide insights into how complex communication signals have developed among animals, including human beings, that establish coupling relationships”, Nao Ota added.

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Giraffe babies inherit spots from their mothers


This 2015 video from South Africa says about itself:

Incredible! Giraffe giving birth in the wild!

Captured by Capture the Wild in the Sabi Sands Reserve, Tydon’s Bush Camp.

From Penn State university in the USA:

Giraffe babies inherit spot patterns from their mothers

October 2, 2018

Some features of a giraffe‘s spot pattern are passed on from mother to baby, according to a new study led by researchers from Penn State. The study also reveals that survival of young giraffes is related to spot pattern, which may help provide camouflage from predators. The new study, published October 2 in the journal PeerJ, confirms a 49-year-old hypothesis about the inheritance of giraffe spots and highlights a new toolset that can be used to study the markings of wild animals.

“Giraffe spot patterns are complex and can be quite different among individuals, but we don’t really know their purpose in the wild”, said Derek E. Lee, associate research professor at Penn State and first author of the paper. “Complex markings can help animals evade predators, regulate their temperature, or recognize family or individuals, all of which can affect their ability to survive and reproduce. In this study, we analyzed survival records and photos of spots of Masai giraffes, and show that spot patterns do affect juvenile survival and are heritable — they are passed from mom to baby.”

Giraffe skin color is uniformly dark gray, but their spots are highly variable in color and shape, ranging from nearly round with very smooth edges to elliptical with jagged or lobed edges. Spot patterns do not change as an animal ages, which allows researchers to identify individuals based on their unique patterns.

This study revealed that newborn giraffes with larger spots and irregularly shaped spots also had increased survival during the first few months of life. This increased survival could reflect better camouflage of these young giraffes, but it also could be related to other survival-enhancing factors, such as temperature regulation or visual communication.

The study also found that two of eleven spot traits measured, circularity — how close the spot is to a perfect circle — and solidity — how smooth and complete the edges are — were significantly similar in mothers and calves. This suggests that these traits are inherited by the calf.

“Dr. Anne Innis Dagg, the first giraffe field researcher in Africa, presented evidence in 1968 that the shape, number, area, and color of spots in giraffe coat patterns may be heritable, but her analysis came from a small zoo population”, said Monica Bond, graduate student in evolutionary biology and environmental studies at the University of Zürich and an author of the paper. “We used wild giraffes and modern imaging and analysis techniques to confirm her conclusions.”

This study also highlights how modern image software and statistical methods can be used to reliably analyze complex coat patterns.

“My hope is that other scientists will use the same tools to measure mammal coat patterns to advance our understanding of what these patterns mean,” said Lee. “Quantifying heritability and fitness consequences of variation in coat patterns could help us understand how and why complex coat patterns evolve in wild animals.”

New bird species discovered in Africa


This 2016 video from Africa says about itself:

Watch this Olive Bushshrike calling and also making the ‘ting-ting-ting’ sound.

Olive bushshrikes are related to a newly discoverd African bird species.

From the American Ornithological Society Publications Office in the USA:

Newly identified African bird species already in trouble

September 19, 2018

Central Africa’s Albertine Rift region is a biodiversity hotspot consisting of a system of highlands that spans six countries. Recent studies have shown that the population of sooty bush-shrikes occupying the region’s mid-elevation forests is a distinct species, and new research from The Condor: Ornithological Applications reveals that this newly discovered species may already be endangered due to pressure from agricultural development.

The newly identified mid-elevation species has been dubbed Willard’s Sooty Boubou, as opposed to the previously recognized high-elevation species, the Mountain Sooty Boubou. The Field Museum’s Fabio Berzaghi (now with the CEA Laboratory for Sciences of Climate and Environment in France) and his colleagues used museum records and bird survey records to analyze the ecological niche occupied by each species, and their results confirm that there is very little overlap between the ranges of the two species — Willard’s Sooty Boubou is found at approximately 1200-1900 meters and the Mountain Sooty Boubou at 1800-3800 meters. In Burundi, Rwanda, and Uganda, 70% of the potential for Willard’s Sooty Boubou lies outside of protected areas and has been converted to agriculture, and the numbers for the Democratic Republic of Congo are only slightly better.

Willard’s Sooty Boubou joins several other imperiled bird species that depend on the region’s mid-elevation forests, which have been largely overlooked by conservation efforts. “The Albertine Rift is a crossroads of amazing biodiversity, dramatic and diverse landscapes, and heartbreaking social and political unrest. It goes from glaciers to volcanoes to plateaus to lakes, with a succession of vegetation types from high-elevation cloud forests to lowland tropical forests”, says Berzaghi. “It is home to gorillas and forest elephants as well as a high number of endemic animal and plant species. Unfortunately, much of the region has gone through never-ending conflicts, with very negative consequences for both humans and biodiversity, and conservation involving local populations is paramount.”

“This paper provides additional data in support of the recognition of Willard’s Sooty Boubou as a species distinct from Mountain Sooty Boubou. Clarification of the niche that Willard’s Sooty Boubou occupies, that of mid-elevation forests, distinct from the higher-elevation Mountain Sooty Bouboy, is important, because these habitats are among the most heavily impacted in Africa from agriculture”, according to UC Berkeley’s Rauri Bowie, an expert on African birds who was not involved in the study. “Conservation agencies have an opportunity to move beyond taxonomic debate and use the models derived from this species to improve conservation outcomes for not only this species, but also a broad set of mid-elevation Albertine Rift endemic vertebrates through protection of mid-elevation forests that have received relatively little protection in comparison to high-elevation montane habitats.”

European small birds’ miles high migration to Africa


This 2015 video is called Red-backed Shrike. Singing male. Lanius collurio.

From Lund University in Sweden:

Small birds fly at high altitudes towards Africa

August 6, 2018

A new study from Lund University in Sweden shows that small birds migrating from Scandinavia to Africa in the autumn occasionally fly as high as 4,000 metres above sea level — probably adjusting their flight to take advantage of favourable winds and different wind layers.

This is the first time that researchers have tracked how high small birds fly all the way from Sweden to Africa. Previous studies have successfully logged the flight height of larger migratory birds.

“We only followed two individuals and two species. But the fact that both of them flew so high does surprise me. It’s fascinating and it raises new questions about the physiology of birds. How do they cope with the air pressure, thin air and low temperatures at these heights?” says Sissel Sjöberg, biologist at Lund University and the Zoological Museum in Copenhagen.

The aim of the study was to investigate whether the measuring method itself works on small birds, that is, to measure acceleration, barometric pressure (air pressure) and temperature throughout the flight using a small data logger attached to the bird.

The data logger was attached to two individuals of different species: the great reed warbler and the red-backed shrike. Among other things, the results show how long it takes for each bird to fly to their destination. The measured barometric pressure showed that the great reed warbler occasionally flies at 3950 metres, and the red-backed shrike flies at 3650 metres.

Both individuals flew the highest above ground across the Mediterranean Sea and the Sahara, but the shrike reached higher flight altitudes closer to its winter grounds in southern Africa.

Sissel Sjöberg thinks it is likely that other small birds fly as high, maybe even higher. But there is no evidence of that yet.

“In this study, we only worked with data collected during the autumn, when the small birds migrate to Africa. There are other studies that indicate that the birds fly even higher when they migrate back in the spring, but we cannot say for sure.”

The small transmitter was developed by technicians at the Centre for Animal Movement Research, CanMove, at Lund University. The study published in the Journal of Avian Biology is a collaboration between Lund University, the University of Copenhagen and the Nature Research Centre in Vilnius.