Madagascar dwarf lemurs, sleep and hibernation


This video from the USA says about itself:

2 May 2013

Two new species of dwarf lemurs have been found hibernating during the lean months of winter in Eastern Madagascar. Scientific Reports, May 2, 2013. An interview with researcher Marina Blanco, PhD, with footage from field research and still images from the Duke Lemur Center. See story here.

From Science News:

Dwarf lemurs don’t agree on sleep

Fat-tailed species dozes during hibernation, but latest tests find different twist in relatives

By Susan Milius

10:00am, September 5, 2016

Contrary to many adorable children’s stories, hibernation is so not sleeping. And most animals can’t do both at the same time.

So what’s with Madagascar’s dwarf lemurs? The fat-tailed dwarf lemur slows its metabolism into true hibernation, and stays there even when brain monitoring shows it’s also sleeping. But two lemur cousins, scientists have just learned, don’t multitask. Like other animals, they have to rev their metabolisms out of hibernation if they want a nap.

Hibernating animals, in the strictest sense, stop regulating body temperature, says Peter Klopfer, cofounder of the Duke Lemur Center in Durham, N.C. “They become totally cold-blooded, like snakes.” By this definition, bears don’t hibernate; they downregulate, dropping their body temperatures only modestly, even when winter den temperatures sink lower. And real hibernation lasts months, disqualifying short-termers such as subtropical hummingbirds. The darting fliers cease temperature regulation and go truly torpid at night. “You can pick them out of the trees,” Klopfer says.

The fat-tailed dwarf lemur, Cheirogaleus medius, was the first primate hibernator discovered, snuggling deep into the softly rotting wood of dead trees. “You’d think they’d suffocate,” he says. But their oxygen demands plunge to somewhere around 1 percent of usual. As trees warm during the day and cool at night, so do these lemurs. When both a tree and its inner lemur heat up, the lemur’s brain activity reflects mammalian REM sleep.

Klopfer expected much the same from two other dwarf lemurs from an upland forest with cold, wet winters. There, C. crossleyi and C. sibreei spend three to seven months curled up underground, below a thick cushion of fallen leaves. “If you didn’t know better, you might think they were dead because they’re cold to the touch,” Klopfer says.

Unlike the tree-hibernators, the upland lemurs take periodic breaks from hibernating to sleep, Klopfer, the Lemur Center’s Marina Blanco and colleagues report in the August Royal Society Open Science. The lemurs generated some body heat of their own about once a week, which is when their brains showed signs of sleep (REM-like and slow-wave).  “My suspicion is that sleep during torpor is only possible at relatively high temperatures, above 20º Celsius,” Klopfer says. Sleep may be important enough for cold-winter lemurs to come out of the storybook “long winter’s nap.”

Omura’s whales, new discoveries


This video says about itself:

3 November 2015

This research was published in the journal Royal Society Open Science in the paper: ‘Omura’s whales (Balaenoptera omurai) off northwest Madagascar: ecology, behaviour and conservation needs’ by Cerchio et al. The doi link for the article is here.

From National Geographic:

This Bus-Size Whale Is Even More Unusual Than We Thought

Scientists are starting to piece together the secret life of the little-seen Omura’s whale, which has a peculiar diet.

By Traci Watson

PUBLISHED February 10, 2016

Well after its discovery a decade ago, the sleek swimmer called the Omura’s whale remained an enigma. Reports of live animals were vague and unconvincing, leaving the whale’s habits and even its markings a mystery.

Now, scientists are starting to piece together the secret life of the little-seen species.

Recent expeditions off Madagascar revealed the whales devouring tiny shrimp-like creatures, as well as guzzling large mouthfuls of “dirty water”—a phenomenon scientists can’t yet explain.

“People see our photos and videos and say, ‘What are they feeding on? I don’t see anything there,’” says Salvatore Cerchio, a marine mammal biologist at the New England Aquarium and leader of the first team to document the whales’ lives.

“Well, I don’t know yet.” (Read about the Madagascar Omura’s Whale Project.)

The whales’ seemingly invisible food supply only adds to the mystique of the Omura’s whale, whose habitat, lifestyle, and social lives make them standouts in the whale world.

Big Moment

Even so, the Omura’s has avoided the limelight. It wasn’t until 2003 that Japanese researchers identified it as a species in its own right rather than a petite version of the similar-looking Bryde’s whale. Genetic data confirmed the whale as its own species in 2006.  …

Even after it was unmasked in the scientific literature, the Omura’s was still known only from dead specimens, some hauled onto whaling ships, others stranded on coastlines.

Then came the Omura’s big moment.

Scouting for dolphins near Madagascar a few years ago, Cerchio spotted some medium-size whales. After the DNA analysis came back, on December 24, 2014, Cerchio learned he’d stumbled onto Omura’s whales—“a very nice Christmas gift,” says Cerchio, a National Geographic explorer.  …

The team’s first round of data, published in October 2015 in the journal Royal Society Open Science, suggest that these Omura’s at least are homebodies. The sightings also suggest the Omura’s sticks to tropical and subtropical waters.

For a whale, that’s doubly unusual. Most whales migrate, often over long distances, and most spend at least some of the year in cooler waters closer to the poles, where food abounds. (See “Life in Antarctica Relies on Shrinking Supply of Krill.”)

Madagascar lemurs’ love life, video


This video says about itself:

Lemur‘s Scent Attracts Females – Animal Attraction – BBC

24 January 2016

Ring tailed lemurs waft their special scent to attract females, but the very latest science suggest that his scent contains clues to a different strength…

The Madagascan fat-tailed dwarf lemur could hold the secret to human hibernation and mankind’s chances of exploring the deepest reaches of the known universe, according to a team of top neuroscientists: here.

Rare Omura’s whales studied in Madagascar


This video says about itself:

23 October 2015

Balaenoptera omurai is known as Omura’s whale and is one of the least known species of whales in the world. Now, researchers have studied around 25 individuals in Madagascar, noticing unique asymmetrical pigmentation on the head:

A – asymmetrical coloration of the lower jaw
B – asymmetrical coloration of the gape
C – leading edge of pectoral fin white from tip to shoulder
D – apparent absence of lateral rostral ridges
E – lightly pigmented blaze originating anterior to the eye
F – lightly pigmented chevron anterior to dorsal fin

The study will continue on whales’ vocalizations, behavior and population characteristics.

From the Woods Hole Oceanographic Institution in the USA:

22 October 2015

New study provides first field observations of rare Omura’s whales

An international team of biologists has made the first-ever field observations of one of the least known species of whales in the world–Omura’s whales–off the coast of Madagascar.

In a paper published October 14, 2015, in the Royal Society Open Science journal, the researchers describe the whales’ foraging and vocal behaviors, and habitat preferences in the shallow waters of coastal Madagascar.

For many years, these marine mammals were misidentified as Bryde’s whales due to their similar appearance–both are small tropical baleen whales with comparable dorsal fins, though Omura’s are slightly smaller in size and have unique markings with a lower jaw that is white on the right side and dark on the left.

In 2003, using genetic data from samples obtained from old whaling expeditions and a few strandings in the western tropical Pacific, scientists determined Omura’s whales were actually a distinct species. But there had been no confirmed records of sightings in the wild and little else has been known about the elusive species until now.

“Over the years, there have been a small handful of possible sightings of Omura’s whales, but nothing that was confirmed,” says lead author Salvatore Cerchio, who led the research while at the Wildlife Conservation Society. He is now at the New England Aquarium (NEAQ) and a guest investigator at the Woods Hole Oceanographic Institution (WHOI). “They appear to occur in remote regions and are difficult to find at sea because they are small–they range in length from approximately 33 to 38 feet–and do not put up a prominent blow.”

So little is known about Omura’s whales that scientists are unsure how many exist or how rare the species is.

“What little we knew about these whales previously came primarily from eight specimens of Omura’s whales taken in Japanese scientific whaling off the Solomon and Keeling Islands and a couple strandings of dead animals in Japan,” Cerchio adds. “This is the first definitive evidence and detailed descriptions of Omura’s whales in the wild and part of what makes this work particularly exciting.”

When Cerchio and his colleagues, who have been conducting field research on marine mammals off the northwest coast of Madagascar since 2007, first spotted an Omura’s whale in the area in 2011, they too believed it was a Bryde’s whale.

“From the little information on their habitat and range, Omura’s whales were not supposed to be in that part of the Indian Ocean,” Cerchio says.

After moving study areas in 2013, the sightings became more frequent and the team noticed the distinct markings– unique asymmetrical pigmentation on the head– that led them to believe the whales might be Omura’s whales.

Over a two-year period, the researchers observed 44 groups and were able to collect skin biopsies from 18 adult whales. The samples were then sent to coauthor Alec Lindsay at Northern Michigan University who performed the DNA analysis that confirmed the whales’ species.

The research team also observed four mothers with young calves. Using hydrophones, they recorded song-like vocalizations that may indicate reproductive behavior.

Cerchio will return to the field in November to do further study on the whales’ vocalizations, behavior and population characteristics. He also hopes to expand the research area in future studies of Omura’s whales, working with colleagues at WHOI to deploy Digital Acoustic Recording Tags (DTAGS) and to study the species in other parts of its range.

Cerchio hopes to produce the first estimate of abundance for any population of Omura’s whales with the work off Madagascar. So far, the team has catalogued approximately 25 individuals through photographic identifications.

What are drift gillnets and how are they hurting whales? Here.

Save Madagascar’s unique wildlife


This video from 2009 says about itself:

Birds & More: Madagascar Safari

80 % of the species are endemic. 6 endemic families of birds. The lemurs were wonderful, so different from monkeys, probably because of a lack of predators. The “spiny” forests are well named and feature the most fascinating baobab trees.

From BirdLife:

Partners come together to save unique wetland

By Martin Fowlie, Thu, 17/09/2015 – 12:21

A new joint project between two BirdLife Partners aims to protect a unique protected area in Western Madagascar.

Over a quarter of a million hectares of different habitats, ranging from the famous Madagascar dry deciduous forests to highly biodiverse wetlands and distinctive marine estuaries, form the Mahavavy-Kinkony wetland Complex. However, the area is threatened with illegal logging, uncontrolled forest fires and pollution, endangering local communities, nature and destroying important natural resources.

NABU (BirdLife in Germany) and Asity Madagascar have now joined forces to protect this unique region. The project is being supported by the German Ministry for Economic Cooperation and Development (BMZ) which is supporting NABU also in other countries such as Ethiopia.

“NABU and Asity will support the local communities in conserving their environment through practical conservation while improving living standards by introducing sustainable alternative income generating activities”, said NABU’s Thomas Tennhardt. “I look forward to the cooperation with our BirdLife Partner in Madagascar.”

In 2001, the region was designated as an Important Bird and Biodiversity Area, because of some of threatened bird species found there, such as Madagascar Sacred Ibis and Madagascar Fish-eagle. Asity has successfully been working with the local communities in the area since 2008.

“In April 2015, the area was awarded permanent protection status by the Madagascan Government, due to ASITYs longstanding work in the region”, said Vony Raminoarisoa, Director of Asity Madagascar.

Asity will now be able to work with local communities to formalise user rights in the area and to create more awareness to safeguard the area. As the local communities rely on the services that this area provides for their daily needs, the protection of these natural resources is absolutely necessary for these communities to survive.

Wild sifakas’ food in Madagascar, new study


This video says about itself:

Infant Development of Diademed Sifaka and Indri, Maromizahaha forest, Madagascar

28 July 2013

The Diademed Sifaka and Indri are the largest species of lemur and are only found in Madagascar. They are both classified as endangered with decreasing populations. This video was made by Jody Weir and Alastair Judkins as part of Jody’s PhD study into comparing the infant development of these two species.

From PLOS ONE:

The Nutritional Geometry of Resource Scarcity: Effects of Lean Seasons and Habitat Disturbance on Nutrient Intakes and Balancing in Wild Sifakas

June 10, 2015

Abstract

Animals experience spatial and temporal variation in food and nutrient supply, which may cause deviations from optimal nutrient intakes in both absolute amounts (meeting nutrient requirements) and proportions (nutrient balancing). Recent research has used the geometric framework for nutrition to obtain an improved understanding of how animals respond to these nutritional constraints, among them free-ranging primates including spider monkeys and gorillas.

We used this framework to examine macronutrient intakes and nutrient balancing in sifakas (Propithecus diadema) at Tsinjoarivo, Madagascar, in order to quantify how these vary across seasons and across habitats with varying degrees of anthropogenic disturbance. Groups in intact habitat experience lean season decreases in frugivory, amounts of food ingested, and nutrient intakes, yet preserve remarkably constant proportions of dietary macronutrients, with the proportional contribution of protein to the diet being highly consistent.

Sifakas in disturbed habitat resemble intact forest groups in the relative contribution of dietary macronutrients, but experience less seasonality: all groups’ diets converge in the lean season, but disturbed forest groups largely fail to experience abundant season improvements in food intake or nutritional outcomes. These results suggest that: (1) lemurs experience seasonality by maintaining nutrient balance at the expense of calories ingested, which contrasts with earlier studies of spider monkeys and gorillas, (2) abundant season foods should be the target of habitat management, even though mortality might be concentrated in the lean season, and (3) primates’ within-group competitive landscapes, which contribute to variation in social organization, may vary in complex ways across habitats and seasons.