Venezuelan Creoles WE

This entry was contributed to Wild Equus by Dr. Jose Luis Canelon of the Catedra Caballo Criollo Venezolano, member and specialist of the Wild Equus Network (WEN).


Species: Equus caballus

Subspecies/Breed/Type: Creole type

Country: Venezuela

Region/Province/Range: Apure. Merida

Population type: Feral and semi feral herds

Estimated Population size: about 400 horses (2015)

Management Authority:  Catedra Caballo Criollo Venezolano

Management Practices: Population Management Strategy is urgently needed to curb genetic erosion

Details of Population

The Venezuelan Creole may be found scattered throughout the country with the highest concentration of individuals in the area of the Llanos (200 meters above sea level) and in the Andean region Sierra Nevada National Park (4,000 meters above sea level) with completely different and extreme geographies. The Llanos had a very dry season for a few months and other season of heavy rains. In the Andean region there are occasional snow and low temperatures regularly.

We have two different groups one completely feral and another semi-feral. the features are typical of the other Creoles. Straight or sub-convex profile, height 1,32-1,49 meters, nostrils in inverted comma, very straight and strong back. Low insertion tail, inclined croup.It is characterized by its hardiness and livestock sense. fully adapted to the environment.

Structure and demographics

Issues worth noting and needed action

In urgent need of special goverment protection to stop genetic erosion.

Baboons don’t play follow the leader – they’re democratic travellers

Robert John Young, University of Salford

Baboons in the wild are known for their highly strategic and hierarchical societies. So when it comes to decisions about where to go, one might expect that some bolshie individuals will direct the group through its habitat. However, a new study of the collective movements of wild olive baboons in Kenya suggests that there are more democratic processes at play.

For wild animals location is everything. The decision to head north instead of south may lead you to a fruiting tree, a pool with water or a place of shelter: all of these things could be the difference between life and death. For that reason, animal movements are never random. Even when searching for things, animals will use specific patterns of movements to sweep their environment. Social animal species like monkeys may not sit down and have a confab over a map, but they still need to make a decision about where the group should be heading.

A baboon in sheep’s clothing?

Numerous theoretical studies show the more you use collective information, the better the decision making process turns out. So it actually makes sense for clever animals like baboons to ignore a dominant individual no matter how much of a despot they are, but instead use a democratic process.

Oliver might be resourceful but look at that silly stroll. He clearly has no idea where he’s going.
Andicat/wikipedia

So far, there has been a limited amount of knowledge about how baboons make decisions about movements. The problem is how to study simultaneous and collective decision making in animals that live in large groups. Baboons typically live in groups of around 100. High accuracy GPS devices mounted on the majority of group members is the answer: this will reveal how animals coordinate their movements relative to one another. I have used this technique in the past on a much smaller scale to investigate the secretive lives of mated pairs of maned wolves in Brazil.

The researchers monitoring baboons in Kenya did just this. When an animal moved off, its influence on the other members of the group was observed. Did the other members follow (that is, did it “pull” them along)? Or did the other members resist the initiative to move off (that is, “anchor” the group). And what happened when several individuals moved off at the same time in different directions?

The researchers found that there was no relationship between position in the hierarchy and pulling the crowd along. In other words, top baboons were as likely to be followers as being followed. This illustrates that leadership and social roles within a social group can be distinct roles. Just because you are the leader does not mean that everyone else in the group treats you like you are infallible in your decision making.

In general individuals were followed when they moved purposefully off in a set direction and were able to rapidly recruit or “pull” other individuals in that direction. This makes sense in that it suggests to other group members that the moving individual’s behaviour is goal driven, for example by looking for food. Perhaps the individual has suddenly remembered the location of a fruiting tree. It would therefore appear that baboons like to follow the crowd – this is similar to quorum sensing behaviour in bees and ants when they are choosing a new nest. The option with the most votes wins.

The 90-degree rule

A big problem of group movement is how to resolve disagreement about the direction to be taken. It is rather like being lost in a strange city on a night out with a group of friends with widely differing opinions about where to go. One effect of this for both humans and baboons is that it delays any decision being made as the conflict is being resolved.

So what’s the solution? It turns out that baboons have a special rule. When the difference between two individuals trying to initiate movements in different directions is less than 90 degrees from one another, then it is resolved by splitting the difference and taking a middle path. However, if the difference of opinion about directions is greater than 90 degrees then individuals accept the choice of one individual over the other. Initiators of movement in a certain direction build up followers, and the individual that has accumulated most followers will end up determining the group’s direction.

You are wrong – the difference is 91 degrees, not 88. Let’s follow Jack.
Rod Waddington/wikimedia, CC BY-SA

It is surprising that something as important as group movement in baboons can be determined by a few simple rules, which are based on the idea that it is better to use the group’s collective knowledge than trust in the opinion of their leader. And perhaps even more so the fact that a dominant individual accepts that it is better to be a sheep than a shepherd in certain situations.

The Conversation

Robert John Young is Professor of Wildlife Conservation at University of Salford

This article was originally published on The Conversation. Read the original article.

The riddle behind zebra stripes

Brenda Larison, University of California, Berkeley

How the zebra got its stripes might at first seem like an esoteric question. But it has fascinated many generations and is embedded in the lore of Africa. It is also a question that offers a great educational tool by helping the general public understand how evolution shapes the variation we see in nature.

I began studying the question out of pure curiosity. But could it be more? Could the answer to why zebras are striped provide any benefits to society? There are many ideas about the advantages that stripes might confer on zebras.

Three ideas have some support: that stripes help zebra escape predation, avoid biting flies, and keeping cool. I’ll take up each of these ideas in turn, while speculating about the societal benefits that could obtain if they were proven to be true.

Predation and the dazzle effect

The most well-known idea about why zebras are striped is that they help them escape predation. The thought is that the dazzle effect of their stripes confuses the predator about either distance, speed, direction of movement, or where one zebra ends and the other begins.

The dazzle effect has already been put to use. In the first world war, ships were painted with bold black and white patterns in the hopes of making them less vulnerable to attack.

Research is mixed as to whether stripes actually lend such an advantage to zebras or might instead make them easier to catch. Once we understand whether stripes make something harder or easier to capture, rest assured that technology will make use of the fact.

Stripes as insect repellent

It has also been suggested that zebra stripes keep disease-carrying flies, such as tsetses and horseflies, from biting. Nagana, a form of sleeping sickness carried by tsetse flies, is a serious deterrent to livestock rearing in parts of Africa. Much research has gone into trying to mitigate this problem.

Researchers are working on not only why zebras are striped, but how. By trying to work out the genetic basis, we might one day be able to breed zebra-striped livestock. I can just see a herd of zebra striped cows contentedly munching away in a swarm of confused tsetse flies.

This solution for livestock would be a double-edged sword, though. The inability to rear livestock is one reason some areas of Africa are safe from human encroachment and are left for wildlife.

At any rate, the waterbuck may have already stolen the zebra’s thunder. Researchers have discovered that waterbuck give off an odour that deters tsetse flies. Collars exuding this smell are now being developed for livestock to wear. This is very much like your dog or cat wearing a flea collar.

Stripes to stay cool

There is another idea about the function of zebra stripes that could have an impact on their survival, and could possibly benefit humans and the rest of the planet. Collaborators and I recently discovered that the strength of striping in one species of zebra, the widespread plains zebra, varies with temperature.

The more stripy zebra are found in hot, tropical climates. Preliminary experiments also suggest that strong black and white stripes may help keep zebras cool under the tropical sun.

Zebra stripes differ.
Brenda Larison

If the biting fly hypothesis is true, temperature may also influence how many parasites they carry. Clearly this matters for zebra in the face of climate change. Zebra in regions of Africa that have seasonally cooler temperatures have subtler striping and often lack stripes on the legs.

Should climate change render these regions hotter, these less stripy zebras may have insufficient ability to thermoregulate and they may be subject to bites by flies that now harbour more parasites. Either of these could pose serious problems for zebras if their populations cannot evolve stronger striping quickly enough.

On a more positive note, if zebra stripes can truly create cooling, imagine an inexpensive cooling system for buildings that requires no energy input once in place. Instead of turning on the air conditioning, just roll out a black and white striped cover onto your roof during hot spells. This could significantly reduce energy usage and help mitigate climate change.

Only time will tell whether any of these ideas pan out. Meanwhile, I work simply to satisfy my curiosity, and hopefully yours.

The Conversation

Brenda Larison is Assistant Adjunct Professor, Department of Ecology and Evolutionary Biology at University of California, Berkeley

This article was originally published on The Conversation. Read the original article.

No wonder we are so fascinated by chimps – they remind us of ourselves

Robert John Young, University of Salford

I can quite happily go to a zoo just to watch the chimpanzees. It is not that the other animals are boring, but that chimps are so fascinating. In recent days the media has reported their drinking of alcohol, their ability to vary smiles and a US move to designate them as endangered. So, what makes chimps so attractive to scientists and the general public alike?

From a scientific point of view they are our closest
genetic relative. We share more than 98% of the same DNA and had a common evolutionary ancestor only 5-7m years ago. So chimpanzee biology and behaviour can tell us much about ourselves. And of course chimps look like us (as do most primate species). Due to these similarities, chimps are one of the most studied primate species of all time.

Head scratcher
International Fund for Animal Welfare Animal Rescue/flickr, CC BY-NC

Chimps were first described approximately 300 years ago and ever since they have appeared in books, films, TV adverts and have even flown in space ships. Their importance in understanding human evolution cannot be denied and this further adds to their high profile within human societies. But during my childhood, chimps were portrayed on the TV as loveable clowns: just think of the Tarzan films or adverts for PG Tips.

However, in my opinion there is something else in the human condition that leads us to be infatuated with chimps. And it is not that they are the most cute and cuddly looking animal. That title goes to the giant panda. Instead it is to do with our human propensity to be voyeurs: we love to watch other people.

Interesting people are those who put on public display their loves, hates and passions. The problem is there is only so much staring and gawping that interesting people (celebrities aside) will tolerate. Chimps provide an alternative outlet for our fascination with others.

What’s the gossip?
Nataša Stuper/flickr, CC BY

Chimps are passionate, scheming, aggressive animals. In many ways they seem to represent the human condition in its most elemental state. When we observe them we are looking at ourselves. But they act without the restrictions that polite society puts on us. And in zoos on wildlife documentaries, groups that are used to being watched by humans are not shy about expressing their desires, be they sexual or otherwise. In other words they are a voyeur’s dream.

To watch a group of chimpanzees is to watch a soap opera unfold before your eyes, but without the pretence of time passing quickly. They live life in the fast lane. Just as one example, chimpanzees are 100 to 1,000 times more aggressive than humans. Even TV soap operas do not show this much action happening in short spaces of time.

Not-so human drama
Tambako The Jaguar/flickr, CC BY-ND

If a male chimp is angry with someone or something then he lets them know in no uncertain terms. This happens not just in terms of bashing things, but also through pronounced facial expressions such as bearing teeth. I think we humans are jealous of chimps because they can vent their aggressive feelings without societal disapproval.

A friend of mine use to work on a project observing captive giant pandas, the world’s most marketed animal. But despite their cuteness they were boring to watch, just eating bamboo, sleeping, defecating every half hour and mating once a year. I challenge anyone to spend a whole day observing them. They just have too little behavioural diversity, expressing interesting behaviours such as aggression or sex at very low frequencies.

Chimps also have a caring side. Once they have attacked and beaten another individual, they will soon go over and give them a hug to prevent this negative interaction spiralling out of control. They show empathy towards sick members of their group. Older individuals are tolerant of the capers of the younger individuals. They live in a loving society where individuals hold hands, hug and kiss in the manner of people from Latin countries. And their partiality to a spot of alcohol has now generated much excitement.

Even when chimps are sitting around doing nothing, as a human observer you sense that something interesting could happen at any second. They never seem to have vacant expressions even when they are resting. They appear to be scheming away, working out how to manipulate other members of their group for food, friendship or sex. Chimps give the impression of being intelligent without the need to be making and using tools to procure food – just sitting down will do.

Cuddle time
Carlos López Molina/flickr, CC BY-NC-ND

Finally, chimps display remarkably strong personalities. Just one day of watching a group in a zoo is enough for you to determine their characters. Some are bold, others timid. Some are very agitated, whereas others seem serene. It is this blend of personalities that creates interesting group dynamics and the script for their soap operatic lives.

We are addicted to chimps because they let us spy on their lives, lives that are so rich and amazing that one, whose name was Flo, even had her obituary published in the Sunday Times newspaper.

The Conversation

Robert John Young is Professor of Wildlife Conservation at University of Salford

This article was originally published on The Conversation. Read the original article.

Pottoka Piornal ponies WE

This entry was contributed to Wild Equus by Lucy Rees, member and researcher of the Wild Equus Network (WEN). You can visit the Pottokas en Piornal website, where you will find more details about her work with the feral pottoka ponies.


Species: Equus caballus

Subspecies/Breed/Type: Pottoka (Basque Pony)

Country: Spain

Region/Province/Range: Sierra de Tormantos, Piornal (Extremadura-Caceres)

Population type: Feral

Management Authority:  Pottokas en Piornal

Estimated Population size: about 40 horses (2015)

Census August 2015

Foals 2015 m 5 (+ 1 that died) f 3

Yearlings    m 4 (b, 3n) f. 3  (d, 2n)

2 y-olds      m 1 (b)  f  4

3 & above   m 5 (b, 4s) f  15

Total 40, m 15, f 25
b= bachelor, s=stallion, n= still with natal band, d=dispersed  – 9/15 mares foaled. = 60%.

Of the 6 that did not foal, 4 were 3 y-o that foaled last year at 2, 1 is 3 y-o,  1 unknown (mare not seen for 3 months)


Details of Population

1200ha. of mountain between 700m and 1500m. , with two deep gorges. Lower-lying areas are oak wood (about 400ha) with scattered chestnut plantations, the latter mainly unavailable to the ponies. The rest is mainly high, dense heather, Spanish broom, bracken and rock, with occasional areas of grass.

Average winter temperature 2.8º; snow may cover areas over 1000m for up to a month. Average summer temperature 20.8º . Water is abundant except in dry summers when all but two springs may dry up. The ponies practice seasonal vertical migration.

The area may also be grazed by up to 600 goats. Occasional red deer, groups of fallow deer, wild boar, fox, martin, jineta, rabbits (few), walkers and cyclists share the area. No large predators.

The population was set up as an open-access study facility for equine researchers and students with non-invasive projects. All ponies can be identified individually and their life history is known. Pottokas are Basque ponies whose DNA variation corresponds to a wild, not domesticated breed. Ours have no management except culling to limit numbers.

Their social organization corresponds to other older feral populations: natal bands, home ranges (around 300ha.), natal dispersal, bachelor bands often joined by dispersing fillies. Three have tamed themselves but the rest cannot be touched although they admit close observation.

Population growth has been limited by culling. In 2014 one entire band (young stallion, old mare, her daughter and grand-daughter) were removed. In 2015 11 ponies (3 y-o stallion, 7 y-o mare, her yearling son, and 7 fillies of 1 and 2 years old were removed). The individuals were chosen to minimize social disruption, being mostly fillies in natal dispersal. To reduce possible conflicts each band was rounded up separately and the youngsters removed.

Despite apparent lack of good forage the ponies are in extremely good condition although lactating mares lose weight at the end of the summer. The ponies show an astonishing ability to self-heal even severe wounds. Parasite burden is negligible.

Structure and demographics

4 single-stallion natal bands, one bachelor band.
The population was set up in 2007/8 in Catalonia with two bands each of one stallion and three mares. On moving the population to its present location in 2011, a 3 year-old unrelated stallion was introduced.

Of the 11 foals conceived in Catalonia 9 were female. In Extremadura 20 colts and 19 fillies have been born.
Mortality:
12 y-o mare, piroplasmosis (Catalonia, 2007)
colt 6 months killed by hippies (c, 2008)
14 y-o stallion, infection from broken tooth (Extremadura, 2014)
12 y-o mare, herbicide poisoning (Extremadura, 2013)
yearling colt, eating plastic bag (E, 2014)
foal 3 weeks (E. 2015)
2 disappeared colts.

About half the fillies become pregnant as yearlings, giving a very fast-growing, female-skewed  population (see culling, below). Fillies that foal at 2 do not foal at 3. Colts begin (inefficiently) to form natal bands at 3 years old.

Issues worth noting and needed actions

a) Legal imperative to microchip, which causes stress and social disruption and is extremely difficult in practice. The European regulations allow exemption in wild or feral ponies but the Extremadura authorities do no recognize this.
b) Damage to fences and walls caused by herds of goats, whose owner refuses to use the gates, cause escapes, social disruption and conflicts with the police.

Bibliography and further reading

Genetic analysis in the basque pony-pottoka breed. Preliminary results

Genetic variability in two spanish horse populations: Preliminary results

Pottoka’s behaviour and training

El caballo al final de la última glaciación en el período postglacial

Hippo gets zebra foal across the river

A cool little video of how a zebra foal drifting away during a Mara River crossing manages to get to shore with the help of a female hippo.
Many tourists visit the Mara River crossings every year, in hopes of witnessing one of the most spectacular and popular animal migrations known. Images portraying the ‘red in tooth and claw’ struggle of Wildebeest and Zebra to get to better grazing grounds abound.
Incidents like these are still few and scattered, but are always a breath of fresh air.
An image of the heroine hippo and the zebra foal on shore.
Incidentally, the same hippo was reported to have helped a Wildebeest calf in a similar incident, only 10 minutes before.
African wildlife - Mother hippo rescues a baby wildebeest in Kenya
Image taken by the Sanctuary Olonana Camp Manager

Read more about these sightings here:

McCullough Peaks horses

This entry was contributed to Wild Equus by Dr. Jason Ransom of Colorado State University, member and specialist of the Wild Equus Network (WEN).


Species: Equus caballus

Subspecies/Breed/Type: American Mustang

Country: United States of America

Region/Province/Range: Park County – Wyoming

Population type: Semi feral-heavily managed

Estimated Population size: between 112-194 horses

Management Authority:  Bureau of Land Management -McCullough Peaks HMA

Images by Jason Ransom. Please respect © copyright!

Management Practices: 

The US Bureau of Land Management has managed this population with periodic round-ups, adopting removed horses to the public. Since 2004, management has more intensively been done using a time-released form of the immunocontraceptive PZP and periodic round-ups.

Details of Population

McCullough Peaks Herd Management Area is located Park County, Wyoming, USA (latitude 44°35‘N, longitude 108°40‘W), and consists of 44,400 ha of primarily open sagebrush steppe with badlands along the western edge. Vegetation consists of large expanses of small shrubs, grasses, and forbs. Pronghorn antelope and mule deer are sympatric with horses here and little natural depredation occurs. Elevations range from 1,200 m to 1,964 m. Mean annual temperature is 8.0°C (range -30.0– 37.8°C) and mean total annual precipitation is 271.2 mm (range=168.9–389.1 mm).

Structure and demographics

Population size reached a high of 495 horses before a large management removal in 2004, and now is maintained between 112 and 194 horses. Bands average 8 horses and many bands closely associate into herds; travelling, feeding, and resting together. At its largest population, bands with more than one stallion occurred, but are now infrequent. Bachelors form loosely associated ephemeral bands or range independently. Genetically, these horses are most related to draft breeds such as the Percheron, probably reflecting much of the early settlement activity around the old west town of Cody. Horses of all colors are in this herd, including Overo, Tobiano, and Sabino paint horses.

Issues worth noting and needed actions

Like most populations in the USA, available habitat for horses is finite and management is necessary to protect all natural resources while attempting to balance the multiple-use mandate for the federal lands where horses live.  The science needed for more-informed management is improving, but many obstacles persist. You can read much more in the 2013 National Research Council report “Using Science to Improve the BLM Wild Horse and Burro Program: A Way Forward

Bibliography and further reading

Additional details about this population, and specifically about behavior and fertility control, can be found in:

Ransom, J.I., Roelle, J.E., Cade, B.S., Coates-Markle, L., and A.J. Kane. 2011. Foaling rates in feral horses treated with the immunocontraceptive porcine zona pellucida. Wildlife Society Bulletin 35:343-352

Ransom, J.I., Cade, B.S., and N.T. Hobbs. 2010. Influences of immunocontraception on time budgets, social behavior, and body condition in feral horses. Applied Animal Behaviour Science 124:51-60

On-going behavior and ecology research from Dr. Ransom can be followed on Twitter @wildequids

Why animals’ pupils come in different shapes and sizes

Gordon Love, Durham University

Wolves and foxes are closely related and share many of the same characteristics. But look at their eyes – where wolves have rounded pupils like humans, foxes instead have a thin vertical line. But it isn’t just canines –across the animal kingdom, pupils come in all shapes and sizes. So why the differences?

It’s a question that has long interested scientists working on vision and optics. In a new study published in the journal Science Advances, colleagues from Durham, Berkeley and I explain why these pupil shapes have developed.

Goats, sheep, horses, domestic cats, and numerous other animals have pupils which vary from fully circular in faint light to narrow slits or rectangles in bright light. The established theory for this is that elongated pupils allow greater control of the amount of light entering the eye. For instance, a domestic cat can change its pupil area by a factor of 135 from fully dilated to fully constricted, whereas humans, with a round pupil, can only change area by a factor of 15. This is particularly useful for animals that are active both day and night, allowing for much better vision in low light conditions.

The cat on the right has got its night-vision goggles on.
Mark Sebastian (L); Kurt Bauschardt (R), CC BY-SA

However, if the only reason for elongated pupils was to control the amount of light entering the eye, the orientation would not be important: horizontal, vertical, or diagonal would all offer the same advantages. Instead, the pupils are almost always horizontal or vertical, which suggests there must be other benefits which explain this orientation.

Pupils fit for every niche

Our work has focused on the visual benefits of vertical and horizontal pupils in mammals and snakes. One of the most interesting factors we found is that the orientation of the pupil can be linked to an animal’s ecological niche. This has been described before, but we went one step further to quantify the relationship.

We found animals with vertically elongated pupils are very likely to be ambush predators which hide until they strike their prey from relatively close distance. They also tend to have eyes on the front of their heads. Foxes and domestic cats are clear examples of this. The difference between foxes and wolves is down to the fact wolves are not ambush predators – instead they hunt in packs, chasing down their prey.

In contrast, horizontally elongated pupils are nearly always found in grazing animals, which have eyes on the sides of their head. They are also very likely to be prey animals such as sheep and goats.

We produced a computer model of eyes which simulates how images appear with different pupil shapes, in order to explain how orientation could benefit different animals. This modelling showed that the vertically elongated pupils in ambush predators enhances their ability to judge distance accurately without having to move their head, which could give away their presence to potential prey.

Sheep can usually see you coming.
Sarah Nichols, CC BY-SA

Grazing animals have different problems to deal with. They need to check all around for prey and they need to flee rapidly in case of attack. Having eyes towards the side of their head helps them to see nearly all around them. Having a horizontal pupil enhances the amount of light they can receive in front of and behind them while reducing the amount of light from above and below. This allows them panoramic vision along the ground to help detect potential predators as early as possible. The horizontal pupil also enhances the image quality of horizontal planes and this enhanced view at ground level is also an advantage when running at speed to escape.

So, vertically elongated pupils help ambush predators capture their prey and horizontally elongated pupils help prey animals avoid their predators.

We realised our hypothesis predicted that shorter animals should have a greater benefit from vertical pupils than taller ones. So we rechecked the data on animals with frontal eyes and vertical pupils and found that 82% are what is considered “short” (which we defined as having a shoulder height of less than 42cm) compared with only 17% of animals with circular pupils.

We also realised that there is a potential problem with the theory for horizontal elongation. If horizontal pupils are such an advantage to grazing animals, what happens when they bend their head down to graze? Is the pupil no longer horizontally aligned with the ground?

We checked this by observing animals in both a zoo and on farms. We found that eyes of goats, deer, horses, and sheep rotate as they bend their head down to eat, keeping the pupil aligned with the ground. This remarkable eye movement, which is in opposite directions in the two eyes, is known as cyclovergence. Each eye in these animals rotates by 50 degrees, possibly more (we can only make the same movement by a few degrees).

Cyclovergence, explained.

There are still some unexplained pupils in nature. For example, mongooses have forward-facing eyes but horizontal pupils, geckos have huge circular pupils when dilated which reduce down to several discrete pinholes when constricted and cuttlefish have “W”-shaped pupils. Understanding all these variations is an interesting challenge for the future.

The Conversation

Gordon Love is Professor of Physics at Durham University.

This article was originally published on The Conversation. Read the original article.

Galician wild ponies WE

This entry was contributed to Wild Equus by Dr.Laura Lagos, member and specialist of the Wild Equus Network (WEN).


Species: Equus caballus

Subspecies/Breed/Type: Galician wild ponies

Special note: Galician Ponies, which belong to the group of Atlantic Ponies or Garranos (Bárcena 2012). There is no evidence of this population of Garranos coming form domesticated populations, and it has even been proposed that the population of wild ponies living in the mountains of Galicia may constitute a subspecies of wild horse, Equus ferus atlanticus (Barcena, 2011). However this hypothesis needs DNA confirmation. Some individuals in the population having certain morphological characteristics have been registered as “Galician pure breed”

Country: Spain

Region/Province/Range: Sierra de A Groba (A Groba Mountain Range), Pontevedra (Galicia)

Population type: Semi feral – slightly managed (Semi-feral according to a classification based on management, wild according to their probable origin.)

Estimated Population size: estimated 850-900 ponies

Management Practices

The traditional management of the Galician ponies includes the removal of the majority of the foals in annual round ups (curro). In the past yearlings were tamed and used for transport, haulage and work in the farms. Today foals are slaughtered for meat for consumption of the local people. In this round ups the manes and tails are shared. In the Sierra de A Groba the management is a bit more intensive, thus ponies are rounded up twice a year and, in these last years during captures ponies are also dewormed and treated for external parasites. In addition, adults are also equipped with micro-chips since it was established in a Galician Decree for domestic horses.

The traditional curros and this old harvesting system of the wild horse population has a great ethnographic value. Today they are still an important social event for locals and are becoming more and more a touristic attraction.

These ponies as a general fact inhabit communal land. It consist on communal forest, called Monte Vecinal en Mano Común (MVMC), belonging to a rural community formed by a group of people living usually in a parish, each parish has their communal forest. The people who traditionally harvest the ponies are called besteiros and they usually are not the owners of the land.

Ponies in these mountains are fire branded. The president of the association has a book with all the marks; some of them have been the same for generations. They are micro chipped since 1-2 years ago.

Details of Population

The Sierra de A Groba is a mountain range, situated in the southwest of Galicia, by the see in one of the most populated areas of Galicia (164 inhabitants per km2 in the surrounding municipalities). Altitudes are between 50-650 m above sea level. The landscapes consist on scrublands dominated by gorse (Ulex europaeus, Ulex minor) and heathers (Erica sp., Calluna vulgaris) together with forest of pines (Pinus pinaster, Pinus radiata) and eucalyptus (Eucalyptus globulus) cultivated for the wood and paper industry. Cattle, sheep, and goats in some areas, are raised in these mountains. Wolves, which are the natural predators of the Galician wild ponies, were extirpated from these mountains in the seventies. The ponies live in an area of about 12,000 ha.

The characteristics of the Galician ponies are reduced size, frequently bay or black coat, curved back, big abdomen and a dense “moustache” which presumably is an adaptation to the consumption of the prickly gorse. The Galician ponies in the Sierra de A Groba are the smallest in Galicia: the average height on shoulders for mares is 119 cm. The moustache is present in about 47% of the mares. In Sierra de A Groba the ponies are called “burras”.

Structure and demographics

Removal of foals means that the sex ratio of adults is artificial and it is maintained at 40-50 mares per stallion. There are 18-20 stallions in the population. Studies on wild ponies in other mountains of Galicia indicate that foaling rate is 0,67 (Lagos 2013), however, in these mountains the habitat is rougher, consequently, the foaling rates are presumably lower.

The census is decreasing. Thirty years ago the population size was 2,000-2,500 ponies (Iglesia 1973) and only 8-10 years ago 1,500 ponies lived in these mountains. The decrease is due to the disappearance of their traditional uses of the ponies, and since 2008 due to the implementation of the regulations for micro chipping of the ponies and other measures which burden this traditional system.

Issues worth noting and needed actions

The implementation of the regulations for micro chipping of the ponies and other measures which burden this traditional system are causing a reduction of the population of ponies and many besteiros giving up this tradition that their families have continued for generations. It is necessary to have regulations adapted to the characteristics of this population of wild ponies.  At least, the exceptions contemplated by the European regulations (EC No 504/2008) for the equidae constituting defined populations living under wild or semi-wild conditions should be applied.

There is an insufficient knowledge of the biological, ecological and cultural value of this population by the managers of the land and the government. It is necessary to disseminate the importance of this population to the public, to the managers of the land and to the government.

Research is needed in order to learn what is the true importance of Galician wild ponies as key species in the habitat, as well as to improve knowledge about their genetics and ecology.

The management of this populations should be more adapted to the biology of these animals.

Bibliography and Further reading

BÁRCENA, F. 2012. Garranos: Os póneis selvagens (Equus ferus sp.) do norte da Península Ibérica. Pages 75-96 en N. Vieira de Brito y G. Candeiras (coord.), Libro de Actas del I Congresso Internacional do Garrano. Arcos de Valdevez. Portugal.

IGLESIA, P. 1973. Los Caballos Gallegos Explotados en Régimen de Libertad o Ca¬ballos Salvajes de Galicia. Tesis, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, 1.205 p

LAGOS, L. 2013. Ecología del lobo (Canis lupus), del poni salvaje (Equus ferus atlanticus) y del ganado vacuno semiextensivo (Bos taurus) en Galicia: interacciones depredador-presa. Tesis, Universidad de Santiago de Compostela, Santiago de Compostela, 458 pp.

LAGOS, L. 2014. O sistema tradicional de aproveitamento dos ponis atlánticos salvaxes nos montes da Groba, Morgadáns e Galiñeiro. Retos no século XXI. Revista del Instituto de Estudios Miñoranos 12/13

Earth’s sixth mass extinction has begun, new study confirms

James Dyke, University of Southampton

We are currently witnessing the start of a mass extinction event the likes of which have not been seen on Earth for at least 65 million years. This is the alarming finding of a new study published in the journal Science Advances.

The research was designed to determine how human actions over the past 500 years have affected the extinction rates of vertebrates: mammals, fish, birds, reptiles and amphibians. It found a clear signal of elevated species loss which has markedly accelerated over the past couple of hundred years, such that life on Earth is embarking on its sixth greatest extinction event in its 3.5 billion year history.

This latest research was conducted by an international team lead by Gerardo Ceballos of the National Autonomous University of Mexico. Measuring extinction rates is notoriously hard. Recently I reported on some of the fiendishly clever ways such rates have been estimated. These studies are producing profoundly worrying results.

However, there is always the risk that such work overestimates modern extinction rates because they need to make a number of assumptions given the very limited data available. Ceballos and his team wanted to put a floor on these numbers, to establish extinction rates for species that were very conservative, with the understanding that whatever the rate of species lost has actually been, it could not be any lower.

This makes their findings even more significant because even with such conservative estimates they find extinction rates are much, much higher than the background rate of extinction – the rate of species loss in the absence of any human impacts.

Here again, they err on the side of caution. A number of studies have attempted to estimate the background rate of extinction. These have produced upper values of about one out of every million species being lost each year. Using recent work by co-author Anthony Barnosky, they effectively double this background rate and so assume that two out of every million species will disappear through natural causes each year. This should mean that differences between the background and human driven extinction rates will be smaller. But they find that the magnitude of more recent extinctions is so great as to effectively swamp any natural processes.

Cumulative vertebrate species recorded as extinct or extinct in the wild by the IUCN (2012). Dashed black line represents background rate. This is the ‘highly conservative estimate’.
Ceballos et al

The “very conservative estimate” of species loss uses International Union of Conservation of Nature data. This contains documented examples of species becoming extinct. They use the same data source to produce the “conservative estimate” which includes known extinct species and those species believed to be extinct or extinct in the wild.

The paper has been published in an open access journal and I would recommend reading it and the accompanying Supplementary Materials. This includes the list of vertebrate species known to have disappeared since the year 1500. The Latin names for these species would be familiar only to specialists, but even the common names are exotic and strange: the Cuban coney, red-bellied gracile, broad-faced potoroo and southern gastric brooding frog.

Farewell, broad-faced potoroo, we hardly knew ye.
John Gould

These particular outer branches of the great tree of life now stop. Some of their remains will be preserved, either as fossils in layers of rocks or glass eyed exhibits in museum cabinets. But the Earth will no longer see them scurry or soar, hear them croak or chirp.

You may wonder to what extent does this matter? Why should we worry if the natural process of extinction is amplified by humans and our expanding industrialised civilisation?

One response to this question essentially points out what the natural world does for us. Whether it’s pollinating our crops, purifying our water, providing fish to eat or fibres to weave, we are dependent on biodiveristy. Ecosystems can only continue to provide things for us if they continue to function in approximately the same way.

The relationship between species diversity and ecosystem function is very complex and not well understood. There may be gradual and reversible decreases in function with decreased biodiversity. There may be effectively no change until a tipping point occurs. The analogy here is popping out rivets from a plane’s wing. The aircraft will fly unimpaired if a few rivets are removed here or there, but to continue to remove rivets is to move the system closer to catastrophic failure.

This latest research tells us what we already knew. Humans have in the space of a few centuries swung a wrecking ball through the Earth’s biosphere. Liquidating biodiversity to produce products and services has an end point. Science is starting to sketch out what that end point could look like but it cannot tell us why to stop before we reach it.

If we regard the Earth as nothing more than a source of resources and a sink for our pollution, if we value other species only in terms of what they can provide to us, then we we will continue to unpick the fabric of life. Remove further rivets from spaceship earth. This not only increases the risk that it will cease to function in the ways that we and future generations will depend on, but can only reduce the complexity and beauty of our home in the cosmos.

The Conversation

James Dyke is Lecturer in Complex Systems Simulation at University of Southampton.

This article was originally published on The Conversation.
Read the original article.

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