Friday, December 20, 2013

Happy Holidays

AaD is taking a holiday break. See you all back in January!

Thursday, December 19, 2013

Common Minke Whale

Balaenoptera acutorostrata
The Common Minke Whale is one of the most abundant whale species on the planet-- there are believed to be around 800,000 of them! They also happen to be the smallest of the Rorquals (baleen whales with throat grooves), and reach only 30ft in length.

Common Minke Whales are found in ocean waters worldwide. They usually swim alone, though sometimes pairs or very small groups are observed. Their small size helps to identify them, as does their slim, sleek body, cloudy-grey skin, white fin bands, and double blowhole.

Like all Baleen Whales, the Common Minke feeds on very small fish and invertebrates, filtering their prey through the baleen plates that hang in their mouths.

Because of their abundance, Minke Whales are common targets for human interaction. They are frequent stars of whale watching tours, but they are also hunted by whalers as well. In the past, Minke Whales were not popular whaling targets because of their small size. However, most larger Baleen Whales are now protected, and the Minke Whales have been thriving in their absence. As a result, countries like Norway and Japan take hundreds of the whales each year. The population is believed to be stable overall, but stocks in certain areas are dwindling.

IUCN Status : Least Concern
Location : Oceans worldwide
Size : Length around 30ft (9m)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Cetacea
Family : Balaenopteridae -- Genus : Balaenoptera -- Species : B. acutorostrata
Images : Rui prieto

Wednesday, December 18, 2013

Dromedary Camel

Camelus dromedarius
Did you know that the Dromedary Camel was domesticated 4,000 years ago? There are around 13 million of these beasts of burden living around the world-- most notably in Africa, the Middle East, and in the deserts of Australia.

Most of these camels are either living as domesticated creatures, or they are surviving in feral populations. Australia, for example, had several thousand camels imported during the late 19th and early 20th century. Today there are nearly a million living in feral groups across the dry western half of the continent. These feral groups live in herds of around 20 individuals, though much larger packs have also been observed. The Camels feed on whatever vegetation they can find, including prickly, thorny plants.

Dromedary Camels are well suited to desert life. Their single hump can store up to 80lbs of fat, which converts to energy when food or water is unavailable. They are masters of co
nserving their energy, and can travel over 100 miles without any extra water! And when they do drink, they drink very fast-- Dromedary Camels can take in 10 gallons of water in as many minutes! Other desert adaptations include their long, double-rowed eyelashes (perfect for keeping sand out), closeable nostril holes, and thick feet with pads that can spread to provide traction and stability over uneven surfaces.

A Dromedary Camel can live to be 40 or 50 years old, and they reach sexual maturity by the age of 4. Young Camels are born without their humps, because they haven't consumed enough extra fuel to fill it with fat.

As adults, the Dromedary Camels are creatures that serves many purposes. They are excellent pack animals, they can pull plows and carts, and they can carry passengers. They also provide milk, meat, and fibers.

Status : Domesticated
Location : Africa, Asia, Australia
Size : Height up to 7ft (2.1m), Weight up to 1,500lbs (680kg)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Artiodactyla
Family : Camelidae -- Genus : Camelus -- Species : C. dromedarius
Images : Public Domain, Witoki

Tuesday, December 17, 2013

Seven-arm Octopus

Haliphron atlanticus
The Seven-arm Octopus has a misleading name. They do actually have eight arms, like all Octopuses do, it's just that one of the arms (the hectocotylus, used for egg fertilization) is often curled up on the males' bodies, making it difficult to see. Females of the species do that have that issue.

Seven-arm Octopuses live in both the Atlantic and the Pacific oceans. It was believed to live only in the former until about fifteen years ago, when one was caught off the coast of New Zealand. Interestingly, these creatures have also been found at both the sea floor AND near the surface, which is unusual for Octopuses.

The species is also notable because they are quite large. In fact, they are the largest Octopuses in the world, and can measure over 11ft in length!

IUCN Status : Not Listed
Location : Atlantic and Pacific Oceans
Size : Length up to 11ft (3.5m)
Classification : Phylum : Mollusca -- Class : Cephalopoda -- Order : Octopoda
Family : Alloposidae -- Genus : Haliphron -- Species : H. atlanticus
Images : RL Hudson

Monday, December 16, 2013

Four-horned Antelope

Tetracerus quadricornis
The Four-horned Antelope is named for the four permanent horns that are found on the males' skulls. That trait actually makes them unique among living mammals. yes, there are some breeds of sheep that have multiples horns, but those are not guaranteed. The male Four-horned Antelope always has that number!

These Antelope are also interesting because of their small size-- they stand less than 2ft tall, which makes them the smallest Bovids in Asia.

When it comes to behavior, the Four-horned Antelope is a solitary creature that feeds on fruits, leaves, and flowers. Males and females remain apart until the breeding season, where the sexes will perform courtship rituals like kneeling and strutting in order to select mates. The gestation period lasts about 8 months, after which one or two young are born. The offspring remain with their mother for about a year, and reach sexual maturity themselves at about 2 years of age.

The species is found in only two countries, India and Nepal, and they are listed as Vulnerable by the IUCN. Their unique horns make them popular hunting targets, and habitat loss has been dimishing their habitat. At present there are around 10,000 individuals left in the wild.

IUCN Status : Vulnerable
Location : South Asia
Size : Height up to 2ft (60cm)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Artiodactyla
Family : Bovidae -- Genus : Tetracerus -- Species : T. quadricornis
Images : Kalyan Varma

Friday, December 13, 2013

Bonelli's Eagle

Aquila fasciata
The Bonelli's Eagle is named for 19th century Italian Ornithologist Franco Andrea Bonelli. It is a large bird, with a body length of around 2ft, and can be found in southern Europe, southern Asia, and throughout most of Africa.

These Eagles are identified by their brown upper-parts, dark-streaked white under-sides, and by the black band at the end of their tail. Adults and juveniles can be told apart by that band-- Juveniles don't have it. Another way to know a Bonelli's Eagle is near? Their call! They make a klu-klu-klu-klee sound while near the nest.

Bonelli's Eagles prefer to live in areas that are neither too open, nor too dense with trees. They typically hunt from trees, swooping down on ground-dwelling prey when spotted. Birds and Lagomorphs are their most common targets.

Did you know that many species of Eagle build multiple nests at a time? The Bonelli's Eagle is one of those species. Pairs mate for life, and will build as many as six nests within their territory. And these are no small nests either-- they can be more than 2m across and 1.5m deep, and the pair will maintain and add to them every year. One theory for the multiple nests is that the birds will have someone else to go should their current nest become unusable.

IUCN Status : Least Concern
Location : Europe, Africa, Asia
Size : Length up to 2ft (60cm)
Classification : Phylum : Chordata -- Class : Aves -- Order : Accipitriformes
Family : Accipitridae -- Genus : Aquila -- Species : A. fasciata
Images : Paco Gomez

Thursday, December 12, 2013

Anomalocaris

Anomalocaris
Anomalocaris is the name of a genus that lived during the Cambrian period... over half a billion years ago!

These ancient relatives to the arthropods of old swam in the seas that covered the planet. Their fossils have been found in places that are (now) as far apart as Canada, China, and Australia.

Anomalocaris grew up to 3ft in length, and had a segmented body that allowed it to swim using an undulating motion. They also had complex, stalked eyes, and two arms covered in barbs that extended from the mouth. The mouth itself was circular, and may have been able to crush hard-bodied prey like Trilobites.

The interesting anatomical features of Anomalocaris made it difficult to identify for many, many years. Different body parts were found independent from one another, and were actually attributed to several different animals, including Jellyfish and Crustaceans. While the first fossils were discovered in 1892, it took until 1985 for scientists to realize all of those fossils belonged to the same animal!

Status : Extinct, lived during the Cambrian ~500 million years ago
Location : Worldwide
Size : Length up to 1m
Classification : Class : †Dinocaridida -- Order : †Radiodonta
Family : †Anomalocarididae -- Genus : †Anomalocaris
Images : Worldlesstech

Wednesday, December 11, 2013

Abyssal Grenadier

Coryphaenoides armatus
Today's animal is one of those deep sea fish that we so uncommonly see alive. Even though they live in all of the world's oceans, the Abyssal Grenadiers normally hang out between 1,000 and 15,000 feet down!

These fish are abundant in the dark depths of the oceans. As adults they can grow nearly a meter in length, though smaller sizes are more common. They feed on other fish, sea urchins, crustaceans, and cephalopods.

Abyssal Grenadiers have a very distinct look to them. They have large heads (featuring large eyes) but bodies that taper out into a tail that completely lacks a caudal fin, along with spined fins that run down both their dorsal and central sides. These fish are known to be very slow-growing, and live as long as 60 years.

Amazingly, while many fish species are suffering, the Abyssal Grenadier populations are booming! They live so far down that they aren't affected by the fishing industry, and between 1989 and 2004 they doubled in number. Scientists don't know much else about them though. Their reproductive habits are unknown, and they have never been kept in captivity.

IUCN Status : Not Listed
Location : Worldwide
Size : Length up to 1m
Classification : Phylum : Chordata -- Class : Actinopterygii -- Order : Gadiformes
Family : Macrouridae -- Genus : Coryphaenoides -- Species : C. armatus
Images : Fishbase

Tuesday, December 10, 2013

Giant Banjo Frog

Limnodynastes interioris
The Giant Banjo Frog, also known as the Great Bullfrog, is an amphibian found in Southern Australia. At a body length of around 9cm, it is the largest Frog in Victoria.

As adults, Giant Banjo Frogs spend most of their time in underground burrows that they dig, keeping themselves moist by absorbing water from the soil around them. They typically are only seen at the surface after it rains, which is when they spawn and hunt for food. During the wet season, the male Frogs will make fast, low pitched calls in order to attract mates.

The Giant Banjo Frogs do their spawning in smaller, slower moving bodies of water like ponds and marshes. They will even lay them in flooded burrows! As Tadpoles they stay in those still or slow-moving zones, maturing slowly before metamorphosing and reaching sexual maturity around 2-3 years of age.

IUCN Status : Least Concern
Location : Australia
Size : Length up to 3.5in (9cm)
Classification : Phylum : Chordata -- Class : Amphibia -- Order : Anura
Family : Myobatrachidae -- Genus : Limnodynastes -- Species : L. interioris
Images : Victoria Dept. of Environment

Monday, December 9, 2013

Mountain Goat

Oreamnos americanus
The Mountain Goat is a large ungulate found only in North America. They are the only species in their genus, but belong to the same subfamily as True Goats and Sheep, Musk Oxen, and Takin.

Mountain Goats live in the Rocky and Cascade Mountains, and they are the largest animals (in their range) to live above the tree line. Males can weigh over 300lbs, while females are usually 2/3 the size.

Despite their large size, the Mountain Goats are very good climbers. Their cloven hooves spread apart for balance, and their footpads help them to maintain traction while traversing areas that have up to 60 degrees of incline. They can also jump up to 12feet in a single leap!

Aside from the size, male and female mountain goats look like-- stark white fut with short beards and black horns. Males live alone most of the time, while females live in small herds with other females and their offspring. Kids are born during the Spring months, and because of the lack of ground cover they have to be up and moving within minutes of birth!

IUCN Status : Least Concern
Location : North America
Size : Height around 3ft (.9m), Weight around 200lbs (90kg)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Artiodactyla
Family : Bovidae -- Genus : Oreamnos -- Species : O. americanus
Images : Robert Shepherd

Friday, December 6, 2013

Greater Siren

Siren lacertina
While it looks like an Eel, today's animal is actually an amphibian-- related to frogs, toads, and salamanders. The Greater Siren is its common name, and it is one of three water-living, practically leg-less Siren species.

The legs are there, but they are very, very small, and can sometimes be totally obscured by the large external gills that these creature have. These creatures are typically brown or black, and have faint stripes as juveniles (though they lose them over time).

Greater Sirens are some of the largest Amphibians found in North America-- they can grow up to 1m in length! They are found in the freshwater rivers and lakes of the southeast United States, where they hunt crayfish, small fish, snails, and other aquatic invertebrates.

The reproductive habits of these Amphibians is unknown. Mating has never been observed! They don't have the organs that typically go along with internal fertilization, but they lay their eggs like an internally fertilized amphibian would. Mysterious!

IUCN Status : Least Concern
Location : North America
Size : Length up to 1m
Classification : Phylum : Chordata -- Class : Amphibia -- Order : Caudata
Family : Sirenidae -- Genus : Siren -- Species : S. lacertina
Image : USGS

Thursday, December 5, 2013

Florida Gar

The Florida Gar is a large freshwater fish found in the waters of the southern United States, especially in Florida and Georgia. They can grow to lengths of 3-4ft, and can be identified by their blotchy dark spots that cover the body and fins.

Florida Gars are able to live in shallow waters that have very little oxygen. They have a special organ, called an air bladder, that allows them to breathe air.

You'll find these fish living in small groups that number between 2 and 10 individuals. They breed in the early spring during a large spawning events where the females lay sticky eggs in the aquatic vegetation and males swim over them and release sperm to fertilize. The parents have no more involvement with the eggs after the spawning event.

As juveniles, Florida Gars feed on insect larvae, plankton, and very small fish. As they grow up they move to larger fish and invertebrates. The Gars hunt by stalking prey very slowly, and then lunging with inedible speed and catching the victims in their jaws.

Florida Gar don't taste very good, so they are not commonly captured by human fishermen. They are abundant through their range and the population is currently stable.

IUCN Status : Not Listed
Location : Southern United States
Size : Length up to 4ft (1.3m)
Classification : Phylum : Chordata -- Class : Actinopterygii -- Order : Lepisosteiformes
Family : Lepisosteidae -- Genus : Lepisosteus -- Species : L. platyrhincus
Image : Kihn Quyen

Wednesday, December 4, 2013

Mauritian Tomb Bat

Taphozous mauritianus
Though named for the island of Mauritius, the Mauritian Tomb Bat is found throughout sub-Saharan Africa and Madagascar. They live in open habitats, including dry-scrub areas where there is little moisture, though they prefer areas with more rainfall.

Outside of the mating season, these bats live in small groups that roost together in cavers, tree cavities, and even on buildings. During the breeding season females roost together in larger groups (several dozen), while males are typically alone. They typically mate once per year, though some populations (depending on location) will make twice. The Bats are polygamous, and males take no part in raising their offspring.

Mauritian Tomb Bats can be identified by their completely white undersides and mottled-gray backs. They have long, narrow arms, and their wingspan is close to double their body length (about 21cm as opposed to 10-11cm).

As with other bats, the Mauritian Tomb Bats use echolocation to hunt at night. But did you know they also sometimes hunt during the daytime? And at those hours they hunt by sight? Moths, butterflies, and other winged insects are their prey of choice. These bats also use audible communication with one another. They chip and screech, though the exact purposes for their calls are unknown.

IUCN Status : Least Concern
Location : Africa
Size : Length up to 11cm
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Chiroptera
Family : Emballonuridae -- Genus : Taphozous -- Species : T. mauritianus
Image : Frank Vassen

Tuesday, December 3, 2013

Pied Kingfisher

Ceryle rudis
The Pied Kingfisher is one of the most common Kingfishers in the world. You'll find them throughout sub-Saharan Africa and Asia, where they live in lowland regions near bodies of water.

Pied Kingfishers are very distinctive in appearance. They have white faces with black masks, stark black bills, and patchy (pied) white and black feathers on their crest, back, and wings. Males and females differ in their chest bands-- males have two, females only one.

Fish are the primary prey of the Pied Kingfisher, though aquatic insects and crustaceans will also be consumed. They hunt by hovering over the water, and once they spot prey they dive in with their large bill first and snatch it up. They can swallow small fish whole, which allows them to hunt longer (rather than returning to a nest to feed).

Pied Kingfishers do their nesting in holes that they dig out in vertical sandbanks. These holes can be more than 4ft long, and can take up to a month to excavate. As many as seven eggs are laid at a time, and mom and dad often have help in raising their brood-- chicks from the previous year often stick around to help out their younger siblings, and non-breeding adults will sometimes also lend a hand.

IUCN Status : Least Concern
Location : Africa and Asia
Size : length up to 7in (18cm)
Classification : Phylum : Chordata -- Class : Aves -- Order : Coraciiformes
Family : Cerylidae -- Genus : Ceryle -- Species : C. rudis
Image : Koshyk

Monday, December 2, 2013

Mexican Wolf

Canis lupus baileyi
The Mexican Wolf is a subspecies of Grey Wolf-- and the most rare subspecies at that. They are listed as Critically Endangered. On top of being close to extinction, they are the smallest (about the size of a German Shepherd), most genetically distinct, and the most southern-living of the North American grey wolves.

Mexican Wolves used to have a range that spread across northern Mexico and the southwest United States. Over time, the large prey mammals that the wolves hunted became more rare, and so the wolves turned to livestock, resulting in widespread wolf hunting. By the 1970s they were extinct in the wild.

Today there are about 75 Mexican Wolves in Arizona, placed there as part of a reintroduction project that began in 1998. The population has been growing, but very slowly. In addition to those wolves, there are about 300 individuals in captivity, with 47 breeding facilities.

Unfortunately those reintroduced Wolves are being hunted, with two shot illegally in 2011. Another troubling issue facing the subspecies is hybridization. Coyotes are common in the area, and research has shown that Coyotes and Mexican Wolves have bred in the past, as genetic markers have been found across the wild populations. Keeping the two species genetically separate is vital to the full recovery of the Wolf populations.

IUCN Status : Critically Endangered
Location : Mexico, southwest United States
Size : Height up to 2.5ft (.8m)
Classification : Phylum : Chordata -- Class : Mammalia -- Order : Carnivora
Family: Canidae -- Genus : Canis -- Species : C. lupus -- Subspecies : C. l. baileyi
Image : Ltshears
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