An Animal A Day
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Erhard's wall lizard
The Erhard's wall lizard (Podarcis erhardii) lives in the Balkan peninsula and the Aegean islands. On the mainland it ranges from Albania, the Republic of Macedonia and southern Bulgaria to the northeastern part of the Peloponnese peninsula in Greece. In the Aegean archipelago it does not occur in Milos or the surrounding islands, where it is replaced by the Milos wall lizard.
Erhard's wall lizard, Podarcis erhardii, male
The length of the lizard's body is about 7 cm; the tail is twice as long. The head is rather wide, and the skin is smooth. The colour and patterning of this species vary a lot. The main colour is typically grey or brown, sometimes green. Females particularly are often striped. On the edges of the back two white stripes border two dark stripes or spotty lines. In the middle of the back may be a dark line. Some males have net-like patterning, where longitudinal and transverse lines and spots mix. The belly and often throat are white, yellow, orange or red, and in the Aegean islands also green, blue or grey. The belly is never spotty, but sometimes there are blue spots in the hind legs.
Erhard's wall lizard lives in dry or rocky places with dense, low bushes. It climbs very well. The lizard populations in the Aegean archipelago inhabit open places, like plant-covered dunes, as well.
Erhard's wall lizard eats arthropods, especially insects. It mates in spring, and lays eggs at the beginning of the summer. The young lizards hatch in September, then measuring 3 cm.
Male Erhard's wall lizard with net-like patterning
Issue #208 -
Bald-faced hornet
The Bald-faced hornet or White-faced hornet (Dolichovespula maculata) is not a true hornet at all. It is actually more closely related to another type of American wasp called the yellowjacket than it is to true hornets like the Asian giant hornet or European hornet.
Bald-faced hornet, Dolichovespula maculata
The Bald-faced hornet lives throughout North America, including southern Canada, the Rocky Mountains, the western coast of the United States, and most of the eastern US. They are most common in the southeastern United States. They are best known for their large gray football-shaped paper nest, which they build in the spring for raising their young. Like the Median wasp Dolichovespula media in Europe, Bald-faced hornets are extremely protective of their nests and will sting repeatedly if disturbed.
Every year young queens that were born and fertilized the previous year start a new colony and raise their young. The workers expand the nest by chewing up wood that mixes with a starch in their saliva, which they spread with their mandibles and legs to dry into paper. The workers also guard the nest and collect nectar and arthropods to feed the larvae. This continues through summer and into fall. As winter approaches, the wasps die, except for young fertilized queens which hibernate underground or in hollow trees. The nest is generally abandoned by winter, and will most likely not be reused. When spring arrives the young queens emerge, and the cycle begins again.
Like other social wasps, Bald-faced Hornets have a caste system made up of the following:
* Queens - Fertile females which begin the colonies and lay eggs
* Workers - Infertile females which have stingers and do the manual labor
* Drones - Fertile males which have no stingers, fertilize the eggs, yet are born from unfertilized eggs.
Bald-faced Hornets also go through a metamorphosis that consists of 4 stages:
1. Egg
2. Larva
3. Pupa
4. Imago or Adult
Issue #209 -
Queensland Lungfish
The Queensland Lungfish (Neoceratodus forsteri) is the sole member of the family Ceratodontidae, and one of the only six lungfish species that remain. Olive or dull brown in colour, it grows to about 150 cm in length, more commonly 100 cm.
Queensland Lungfish, Neoceratodus forsteri
It is native to the Burnett and Mary River systems of south-east Queensland, but has been introduced into other nearby rivers, including the Brisbane River. It prefers still or slow-flowing water with at least some aquatic vegetation on the banks, particularly deep pools.
Also known as the Australian Lungfish, this creature normally uses its gills for respiration, but is also capable of taking in oxygen from the air when water quality is poor, or there are low dissolved oxygen levels, such as when water temperatures are high during summer.
This species belongs to a very ancient group Sarcopterygii the fleshy-finned fishes which is over 400 million years old. Fossils of fish identical to N. forsteri have been dated at over 100 million years which makes this species one of the oldest extant vertebrate species.
Previously lungfish were considered to be the direct ancestors of amphibians, but now a common ancestor is recognised, although lungfishes did appear early in the history of vertebrates.
Spawning involves individual pairs of fish and complex behaviour, however, unlike other lungfish species Australian lungfish do not exhibit parental care.
Primarily carnivorous, the diet consists mainly of small fish, frogs and tadpoles and invertebrates, however they have on occasion been observed to consume some vegetable matter.
Issue #210 -
Tasmanian giant freshwater crayfish
The Tasmanian giant freshwater crayfish, Astacopsis gouldi, is the largest freshwater invertebrate in the world. The species in only found in Tasmania, and is listed as a vulnerable species due to habitat loss and illegal fishing.
Tasmanian giant freshwater crayfish, Astacopsis gouldi
Individuals of over 5 kg in weight and over 80 cm long have been known in the past, but now, even individuals over 2 kg are rare. The species is only found below 400 m above sea level in Tasmanian rivers flowing north into the Bass Strait (with the exception of the Tamar). The specific epithet gouldi commemorates the Australian naturalist John Gould.
A. gouldi is very long-lived and reproduces slowly, with the result that fishing this species has had a great impact on its abundance, and also explains why the largest individuals now found are smaller than previously. This species was listed as "vulnerable" under Australian law, and it is now illegal to catch A. gouldi under any circumstances.
Conservation status: Vulnerable
Issue #211 -
Laysan Rail
The Laysan Rail (Porzana palmeri) was a tiny inhabitant of the North West Hawaiian atoll of Laysan. This small island was and still is an important seabird colony, and sustained a number of endemic species, including the rail. It became extinct due to habitat loss, feral rats, and the Second World War.
Laysan Rail, Porzana palmeri. Illustration from Rothschild (1893-1900)
Habitat and Description
Laysan is considered on of the most important seabird colonies in the United States. It has thousands of Black-footed Albatross, Laysan Albatross as well as shearwaters and terns. The island also held 5 unique landbirds, including the Laysan Rail. It was a small (15 cm) bird, flightless member of the rail family, an opportunist that would feed on invertebrates and the eggs of seabirds. It was an aggressive feeder that would fight off other species, particularly the Laysan Finch. It was endemic to the Laysan, though some authors have noted that there were records on other Hawaiian islands.
Extinction
The extinction of the Laysan Rail is particularly unfortunate as it could have easily been avoided. The rail was initially threatened when rabbits were introduced to Laysan. With no predators to control their numbers the rabbits soon ate the entire vegetation cover on the island. This turned the island into a barren dust bowl, sending the Laysan Millerbird and the Laysan Honeycreeper (both subspecies endemic to the island) to extinction. The Laysan Finch and Laysan Duck both survived by eating shore flies and scavenging bird eggs and carrion. The rail is believed to have become extinct on Laysan in the 1920s.
The story did not end there, however. The rail had been introduced to Midway Atoll in 1891, and had thrived on the island. Once the rail had become extinct on Laysan moves were made to both re-introduce the rail to its old home and take some to the main islands of Hawaii, along with Laysan Finches, to form a experimental population. This would have safeguarded the species. Rails were collected for this, however the idea was held up by red-tape, some people in the United States Biological Survey were concerned that the Laysan Finch, if it escaped on the main islands, would become a serious pest. The move of some of the birds to safety was therefore held up because of concerns about the finch.
The population on Midway survived until the Second World War, when in 1943 a landing craft accidentally broke free during a battle and rats were introduced on to the island. Within two years the species was extinct. A final irony was that the last man to see a Laysan Rail alive was warden Ed Caum, the man who had refused their export to Honolulu.
The scientific name honours Henry Palmer, who collected in the Hawaiian Islands for Walter Rothschild.
Conservation status: Extinct (1945)
Issue #212 -
American Keuda
The American Keuda (pronounced KEW-da) is a type of cat. The Keuda type is currently under development to become a standardized breed. The roots of the breed are from a 1980s study called the "Kitten Evaluation Under Direct Assessment" which was meant to determine the characteristics which led to superior barn cats in the Southwestern United States. Barn cats gathered from the study area (Oklahoma, New Mexico, and Texas) were bred with each other to develop the breed.
American Keuda
The American Keuda has some pronounced similarities with the Egyptian Mau breed. It is an open and controversial question whether this reflects an Egyptian Mau contribution to their gene pool or whether cats with Mau-like traits are superior barn cats. In the latter case, these traits would be reinforced over time and would not necessarily require a Mau contribution to the gene pool. Since the Egyptian Mau itself was redomesticated from feral Egyptian cat populations in the mid-1950s, it may represent a superior feral cat type, closely reproduced in the deserts of the American Southwest in the Keuda, but with no direct genetic connection to that breed.
American Keuda cats share many physical similarities with the Mau, including body type and a belly flap, not seen in other breeds. Since the belly flap adaptation allows extra extension when running, and thus more speed, this would be a successful adaptation for any cat that needed speed, like a barn cat. Keudas also share a high level of intelligence and athleticism with the Mau, as well as speed and a love for warm conditions. One marked difference between the Keuda and the Mau is the wide diversity of appearance the Keuda displays. While some Keudas look strikingly like Maus, they may also look like a Siamese, Havana Brown, cats of other breeds or mixed breed cats. Keuda cats display a much wider variety of coat colors and patterns than do Maus.
Issue #213 -
Sugar Glider
The Sugar Glider (Petaurus breviceps) is a small gliding possum native to eastern and northern mainland Australia, New Guinea, and the Bismarck Archipelago, and introduced to Tasmania.
It is around 16 to 20 cm (6.3 to 7.5 in) in length, with a slightly longer tail, and weighs between 90 and 150 grams (3 to 5.3 oz). The fur is generally pearl grey, with black and cream patches at the base of the pink ears. The tail tapers only moderately and the last quarter of it is black, often with a white tip. The muzzle is short and rounded. Northern forms tend to be brown coloured rather than grey and, as predicted by Bergmann's Rule, smaller.
Sugar Glider, Petaurus breviceps
The most noticeable features of its anatomy, however, are the twin skin membranes called "patagium"s which extend from the fifth finger of the forelimb back to the first toe of the hind foot. These are inconspicuous when the Sugar Glider is at rest — it merely looks a little flabby, as though it had lost a lot of weight recently — but immediately obvious when it takes flight. The membranes are used to glide between trees: when fully extended they form an aerodynamic surface the size of a large handkerchief.
Sugar Gliders can occupy any area where there are tree hollows for shelter and sufficient food. Their diet varies considerably with both geography and the changing seasons, but the main items are the sap of acacias and certain eucalupts, nectar, pollen, and arthropods. They are difficult to see in the wild, being small, wary, and nocturnal, but a sure sign of their presence is the stripping of bark and tooth marks left in the soft, green shoots of acacia trees.
The gliding membranes are primarily used as an efficient way to get to food resources. They may also, as a secondary function, help the Sugar Glider escape predators like goannas, introduced foxes and cats, and the marsupial carnivores that foxes, cats, and Dingos largely supplanted. The ability to glide from tree to tree is clearly of little value with regard to the Sugar Glider's avian predators, however, in particular owls and kookaburras.
Although their aerial adaptation looks rather clumsy and primitive by comparison with the highly specialised limbs of birds and bats, Sugar Gliders can glide for a surprisingly long distance — flights have been measured at over 50 meters (55 yd) — and steer effectively by curving one or other of the gliding membranes (patagium). They use their hind legs to thrust powerfully away from a tree, and when about 3 meters (3 yd) from the destination tree trunk, bring their hind legs up close to the body and swoop upwards to make contact with all four limbs together.
In suitable habitats, they are common, often reaching densities of 1 per 1,000 square meters provided that there are tree hollows available for shelter. They live in groups of up to 7 adults, plus the current season's young, all sharing a nest and defending their territory. Adult males mark the territory with saliva and with scent glands, and also mark members of the group with the scent produced by separate glands on the forehead and chest. Visitors which lack the appropriate scent marking are expelled violently. The dominant male mates more frequently with the female of the group than the other males, and does most of the scent marking. When an adult member of the group dies, it is normally replaced: by one of the group's own offspring if female, but by an outsider if male.
In the more temperate south, breeding starts in mid-winter (June or July). In the north, there seems to be no particular breeding season. Two young per female is typical; they remain in the pouch for about 70 days, and after leaving it stay inside the nest for another 40 or 50 days, then begin to forage outside, usually under the care of the mother. The young are normally ejected from the group territory at 7 to 10 months of age. Sometimes they form new groups if an area is vacant, but competition for territory is fierce and not many survive the first months of independent life. In captivity, they may live up to fifteen years.
Unlike many native animals, particularly smaller ones, Sugar Gliders are not endangered. Despite the massive loss of natural habitat in Australia over the last 200 years, they are adaptable and capable of living in surprisingly small patches of remnant bush, particularly if they do not have to cross large expanses of clear-felled land to reach them. Several close relatives, however, are endangered, particularly Leadbeater's Possum and the Mahogany Glider (which, to the non-expert, looks almost exactly like a Sugar Glider).
Like all native creatures they are protected by law in Australia where it is illegal to keep them as pets, or to capture or sell them without a licence (which is usually only issued for bona-fide research). However, they are not difficult to breed in captivity under the right conditions, and small numbers have been legally exported to America where they have formed a breeding population for sale as pets. The Sugar Glider is a popular pet because of its sweet, lively, inquisitive nature, but is illegal in certain jurisdictions, such as California, Georgia, Hawaii, Maine, and Alaska. Many other states in the United States require a permit.
A sugar glider featured on the reverse of the Australian 1 cent coin, until it was withdrawn from circulation in 1991.
Conservation status: Lower risk
Issue #214 -
Palm Cockatoo
The Palm Cockatoo, Probosciger aterrimus, is a large black parrot of the cockatoo family. It is found in northern Queensland and New Guinea. It measures around 55-60 cm in length and weighs between 500-1,000 g. It is a distinctive bird with a large crest and one of the largest bills of any parrot (only the Hyacinth Macaw's is larger). The bill is also unusual as the lower and upper mandibles do not meet for much of its length, allowing the tongue to hold a nut against the top mandible while the lower mandible works to open it. The Palm Cockatoo also has a distinctive red gape that changes colour when the bird is alarmed or excited.
Palm Cockatoo, Probosciger aterrimus
The Palm Cockatoo makes four different kinds of vocalisations. It also has a unique display where the bird drums a large branch against a dead bough or tree, creating a loud noise that can be heard up to 100 m away.
The Palm Cockatoo is currently listed as near-threatened. It is in high demand for the pet trade due to its unusual appearance, but does not breed well in captivity, requiring the removal of wild birds, and is therefore listed as CITES I. It is still relatively common in Cape York, but is threatened there by habitat loss.
Alfred Hitchcock once used one to play an "evil bird" in one of his movies due to their striking and unusual appearance.
Conservation status: Lower risk (lc)
Issue #215 -
Banded Krait
The Banded Krait (Bungarus fasciatus) is an easily identifiable snake due to its alternate black and yellow bands. Its venom is neurotoxic and is about 10 times or more venomous than a Cobra, though it rarely bites and few deaths have been attributed to its bite. As such any bite is fatal as anti-venom is not commonly available.
Banded Krait, Bungarus fasciatus
Distribution
It is found in the Indian subcontinent through Burma, Thailand, Indochina and southern China to Malaysia and the main Indonesian islands of Borneo, Java and Sumatra and Singapore.
Habitat
They may be seen in a variety of habitats ranging from forests to agricultural lands. They inhabit termite mounds and rodent holes close to water, and often live near human settlement especially villages because of their supply of rodents and water. They prefer the open plains of the countryside.
Behaviour
Though very poisonous, it is a shy snake, difficult to sight, and is mainly nocturnal in feeding habit. Snake handlers mention that, except in the night, they are the easiest of the venomous snakes to handle.
Issue #216 -
Brown cockroach
The Brown cockroach (Periplaneta brunnea) is a large species of cockroach, winged, and growing to a length of 1 1/4"-1 1/2". It is dark, reddish brown in colour.
Brown cockroach, Periplaneta brunnea
It is can be found in the southern United States, and in tropical and subtropical climates, and can be found in many locations throughout the world, due to its travels via shipping and commerce between locations. In cold climates, it is likely mostly found near human habitat due to its lack of cold tolerance.
The insect is believed to have originated from Africa, but had become established in the southern U.S. by the time that it was given its name.
The insect is very similar in appearance to the American cockroach, and may often may be mistaken for it.
The insect can travel quickly, often darting out of sight when someone enters a room, and can fit into small cracks and under doors despite its fairly large size. It is known to be very mobile, it also has wings which allow it to be quite a capable flier.
It prefers warmer climates and is not cold tolerant, however, it may be able to survive indoors in colder climates. It does well in moist conditions but also can tolerate dry conditions as long as water is available.
The insect is usually found outdoors in warm climates, where it can be found under the bark of trees, in brush, and crevices.
Issue #217 -
Pilot fish
The Pilot fish (Naucrates duclor) is a carnivorous fish that is a horse mackerel and belongs to the Carangidae family of fishes. It is widely distributed and lives in warm or tropical open seas.
Pilot fish, Naucrates duclor
The pilot fish is known for following large vessels and sharks, where it apparently feeds on parasites and leftovers. Pilot fish and sharks enjoy a strange symbiotic relationship. It is extremely rare that a shark will feed on a pilot fish, although the smaller fish are frequently observed swimming into sharks' mouths to clean away fragments of food from between their teeth. Anecdotal evidence suggests that ancient Greek sailors believed that pilot fish, which would appear around their ships when they were close to land, were leading (or piloting) them back to port, and so they were named. It is sometimes suggested that pilot fish were thought to be piloting larger fish to food as well.
The pilot fish has distinctive black and white markings; this observation has led to similar markings' being used in decals supplied as shark protection for surfboards.
The Shark Tank column of Computerworld magazine uses the term "pilot fish" metaphorically to describe computer consultants and other "techies" swimming with the sharks of corporate IT departments.
Issue #218 -
Velvet worm
Onychophora (also called velvet worms) are segmented, caterpillar-like, terrestrial animals somewhat resembling both arthropods and annelid worms. They are generally regarded either as a class of arthropods or as a separate phylum (in which case they are the only animal phylum to include no marine species). About 110 modern species are known separated into two families, with 10 genera. They live in many tropical and subtropical regions worldwide including Mexico, Central America, South America, Africa, Australia and New Zealand. Modern species are fairly small; at least one species reaches lengths of 20 cm (about 8 inches). The best known modern form is Peripatus which was described by Guilding in 1825.
Velvet Worm (phylum Onychophora) from the Amazon Rain Forest in Peru.
Onychophores are apparently descended from some segmented form but have lost their overt segmentation except for the head which is composed of three segments. There are two antennae on the first head segment and usually a pair of eyes. The second head segment has a mouth. Unlike arthropods, the animal does not have a stiff exoskeleton. Their skin (cuticle) is covered with fine hairs (papillae) giving a velvet-like feel and accounting for their popular name of "velvet worms". The cuticle is shed periodically to allow growth. Although the body has several dozen repeated leg pairs, it is not actually segmented. Onychophores are coelomates with a haemocoel. The entire structure is supported by blood pumped by a heart. Legs are tipped by chitinous claws and walking pads used on smooth surfaces. Onychophores breathe through always-open passages in the skin trachea. As a result, all known species require a humid environment to avoid desiccation.
Modern onychophores are predators that are able to immobilize animals several times their own size with a gluey substance that they eject from glands in their head. They can immobilize targets up to 30 cm away.
Onychophores are thought to be closely related to the arthropods. Possible marine onychopores are known from the Lower Cambrian -- Aysheaia, Hallucigenia -- and possibly the late Pre-Cambrian -- Xenusion. A single fossil terrestrial genus is known from the Pennsylvanian of Illinois and some Tertiary specimens are reported from Caribbean amber.
Extant families
- Peripatidae
- Peripatopsidae
Issue #219 -
Protoceratops
Protoceratops is a sheep-sized, herbivorous ceratopsian dinosaur from the Upper Cretaceous of Mongolia. There are two recognized species: the type species P. andrewsi and the newly named P. hellenikorhinus. Unlike later ceratopsians, it lacked well-developed horns.
Protoceratops skeleton at Wyoming Dinosaur Center
Protoceratops had a large neck frill, which may have served to protect the neck, to anchor jaw muscles, or to impress other members of the species. In 1971, A Velociraptor was found clutched around a Protoceratops in Mongolia. It is believed both died at once while fighting, when they were either surprised by a sand storm or buried when a sand dune collapsed on top of them.
The related protoceratopsian Leptoceratops is known from North America.
Folklorist Adrienne Mayor has suggested that skulls of this dinosaur found by ancient peoples may have been at the root of mythical beasts such as the griffin; the horse-like body with the bird-like beak being particularly notable.
Conservation status: Fossil
Issue #220 -
French Bulldog
The French Bulldog is a dog breed that first emerged in France in the mid- to late 19th century.
French Bulldog
Appearance
French Bulldogs average 22 to 25 pounds (10 to 12 kg) and are considered out-of-breed if they are over 28 pounds (13 kg). Their physical appearance is characterized by naturally occurring 'bat ears' that are pointy and stick straight up. Their tails are naturally short, not cropped. Otherwise, their body shape is similar to that of an English Bulldog.
The honey pied coat is a fairly rare coloring.
There are several color variations allowed by the AKC that are disallowed in Europe, including the cream color. French Bulldogs have their own variations in the amount of brindle, darkness of their coat, and amount of white areas.
Temperament
The French Bulldog is a gentle breed that typically has a happy-go-lucky attitude. Like many other companion dog breeds they have high energy and prefer interaction with humans to interaction with other dogs. They do well around other dogs and small children, though they should be monitored closely during their initial encounters; they tend to shy away from teasing or rough play. They tend to not bark a lot and are of small size; these qualities may make them a good candidate for apartment living.
Health
European French Bulldogs typically are born naturally, while North American French Bulldogs are born by Caesarean section.
Due to the nature of their short windpipe, they tend to have breathing difficulties, and can easily suffer problems in hot weather as a result. For the same reason, veterinarians consider them difficult to intubate for surgery. Otherwise, they are generally considered a healthier breed than the English Bulldog, with a lower occurrence of problems such as hip dysplasia. Like their larger cousin the English Bulldog, French Bulldogs are prone to gastro-intestinal problems such as gas.
Life expectancy is 10 to 12 years.
Brindle is a more common color for the French Bulldog
History
The breed emerged as English Bulldogs were bred with Toy Bulldogs by the artisan community in Paris, after Toy Bulldogs were marginalized by British kennel clubs as weakening the English Bulldog breed. Toy Bulldogs were popular amongst the artisan and gay communities in Britain. The breeding of the minuscule Toy Bulldog (averaging 8 pounds (3.5 kg)) and the English Bulldog (which can vary in size, but is usually around 50 pounds (23 kg)) produced the medium-sized French Bulldog.
Alternative names: Bouledogue Français
Common nickname: Frenchie
Country of origin: France
Issue #221 -
False Killer Whale
The False Killer Whale (Pseudorca crassidens) is a cetacean and one of the larger members of the oceanic dolphin family (Delphinidae). It lives in temperate and tropical waters throughout the world. As its name implies, the False Killer Whale shares characteristics with the more widely known orca ("killer whale"). The two species look somewhat similar and, like the orca, the False Killer Whale attacks and kills other cetaceans.
False Killer Whale, Pseudorca crassidens
The False Killer Whale has not been extensively studied in the wild by scientists - much of the data about the whale has been derived by examining stranded animals.
The species is the only member of the Pseudorca genus.
Physical description
This dolphin has a slender body with a dorsal fin that may be more than a foot high. One of the species' distinguishing characteristics is a bend and bulge (usually called the "elbow") half-way along each of the flippers. The tips of the tail fin are pointed and the middle of the tail has a distinct notch. The False Killer is uniformly coloured a dark grey to black. The False Killer Whale is a social animal - it lives in groups of 10-50. It is a fast and very active swimmer. It may breach or jump clear of the water and will often land on its side with a big splash. On other occasions the dive may be very graceful - leaving very little wake at all. It will readily approach boats and bow- and wake-ride. It may also emerge from the water head held high upwards and with the mouth open - revealing some of its 48 teeth.
The dolphin grows to about 6 m long, may weigh 1,500 kg and lives for about 60 years.
Population and distribution
Although not often seen at sea, the False Killer Whale appears to have a widespread, if rare, distribution in temperate and tropical oceanic waters. They have been sighted in fairly shallow waters such as the Mediterranean Sea and Red Sea as well as the Atlantic Ocean (from Scotland to Argentina), the Indian Ocean (in coastal regions) and the Pacific Ocean (from the Sea of Japan to New Zealand and the tropical area of the eastern side).
The total population is unknown. The eastern Pacific was estimated to have in excess of 40,000 individuals and is probably the home of the largest grouping.
False Killer Whale range
Human interaction
The False Killer Whale has been hunted, but not extensively in the West Indies and Indonesia. Japan usually kills a small number of individuals each year.
False Killers have long caused anger amongst fishermen fishing for tuna and yellowtail. The dolphins take the fish from the longlines used by the fishermen. This led to a concerted effort from Japanese fisherman working from Iki Island to deplete the species in the area - 900 individuals were killed for this purpose between 1965 and 1990.
100 False Killers were beached at Geographe Bay, Western Australia on 2 June 2005. The pod of 160 were moved back out to sea with only one death after the intervention of 1,500 volunteers coordinated by the Department of Conservation and Land Management.
Conservation status: Lower risk
Issue #222 -
Harris's Hawk
The Harris's Hawk or Harris Hawk (formerly the Bay-winged Hawk), Parabuteo unicinctus, is a medium-large bird of prey which breeds from the southwestern USA south to Chile and central Argentina. It is the only member of the genus Parabuteo (Ridgway, 1874).
Harris's Hawk, Parabuteo unicinctus
Its habitat is sparse woodland and semi-desert, as well as marshes (with some trees) in some parts of its range (Howell and Webb 1994). It nests in a tree and lays 2–4 eggs, incubated for 28 days to hatching.
It has blackish brown plumage with chestnut forewings (above and below) and thighs. The end of the tail and the rump are white. It has a length of 60 cm and a wingspan of 1.2 m; the average weight is about 900 g (2 pounds). Females are typically 10% bigger than males.
A Harris's Hawk can just about catch and kill a rabbit, but its natural prey are small rodents and reptiles.
Harris's Hawks' social behavior is unusual for raptors. Young may stay with their parents for up to three years, helping to raise later broods. They also hunt together, groups of two to six birds often cooperating to flush and then capture prey. In contrast, the vast majority of raptors are solitary hunters.
This social behavior gives Harris's Hawks an easygoing nature that makes them desirable captive birds. Since about 1980, Harris's Hawks have been increasingly used in falconry and are now the most popular hawks in the West (outside of Asia) for that purpose, as they are the easiest to train and the most affectionate.
Hunting with Harris's Hawks often works best with two or more birds. (In contrast most other raptors cannot be flown together, as they will attack each other.) When prey is flushed, the birds can work together to corner the animal – compensating for their relatively low acceleration and speed. Harris's Hawks will happily treat the falconer as a hunting partner, and will follow from tree to tree and perch until the falconer flushes a rabbit from the bushes!
The Harris's Hawk is now widely used in European towns to scare pigeons and Starlings. Many airports use falconers to scare these birds away from the land around runways and reduce the risk of birdstrikes on planes.
John James Audubon gave this bird its English name in honor of his ornithological companion, financial supporter, and friend Edward Harris.
Issue #223 -
Aldabra Giant Tortoise
The Aldabra Giant Tortoise (Geochelone gigantea) is one of the largest tortoises in the world. Similar in size to the famous Galapagos Giant Tortoise, its carapace averages 120 cm in length. The average weight of a male is around 250 kg, but one male at the Fort Worth Zoological Park weighs over 360 kg.
Aldabra Giant Tortoise, Dipsochelys dussumieri, from Aldabra atoll in the Seychelles, at Bristol Zoo, Bristol, England.
Physical Characteristics
The shell is a dark gray or black color with a high domed shape. It has stocky, heavily scaled legs to support its heavy body. The neck of the Aldabra Giant Tortoise is very long, even for its great size, which helps the animal to exploit tree branches up to a meter from the ground as a food source.
Females are generally smaller than males, with average specimens measuring about 90 cm in length and weighing around 150 kg.
Diet
Primarily herbivores, Aldabra Tortoises will eat grasses, leaves, and woody plant stems. They occasionally indulge in small invertebrates and carrion, even eating the bodies of other dead tortoises. In captivity, Aldabra Giant Tortoises are known to enjoy fruits such as apples and bananas as well as compressed vegetable pellets.
There is little fresh water available for drinking in the tortoises' natural habitat, therefore they obtain most of their mositure from their food.
Breeding
Aldabra Giant Tortoises reach sexual maturity when they attain about half their final size. Interestingly, it seems that reaching sexual maturity is determined by size, not by age.
After mating from February to May, Females lay between 9 and 25 rubbery eggs in a shallow, dry nest. Usually, less than half of the eggs are fertile. Females can produce multiple clutches of eggs in a year. After incubating for about 8 months, the tiny, independent young hatch between October and December.
Range and Habitat
The main population of the Aldabra Giant Tortoise resides on the islands of the Aldabra Atoll in the Seychelles. Another group of the animals resides on the island of Zanzibar. The tortoises exploit many different kinds of habitat including grasslands, low scrub, mangrove swamps, and coastal dunes.
A peculiar kind of habitat has evolved due to the pressures of the tortoises: "tortoise turf," a comingling of 21 species of grasses and herbs. Many of these distinct plants are natually dwarfed and grow their seeds not from the tops of the plants, but closer to the ground to avoid the tortoises' close cropping jaws.
As the largest animal in its environment, the Aldabra Tortoise performs a role similar to that of the elephant. Their vigorous search for food fells trees and creates pathways used by other animals.
Behavior
Aldabra tortoises are found both individually and in herds, which tend to gather mostly on open grasslands. They are most active in the mornings when they spend time browsing for food. They dig underground burrows or rest in swamps to keep cool during the heat of the day.
While they are characteristically slow and cautious, they are capable of appreciable speed, especially when tempted with a treat. They are also known to attempt perilous acrobatic feats, rising precariously on their hind legs to reach low branches. They risk death by tipping onto their backs and being unable to right themselves.
They are also excellent swimmers, being neutrally buoyant. This allowed the spread and eventual speciation of many kinds of related (and now extinct) tortoises across the Indian Ocean.
The tortoises are not domestic or tame, but they are remarkably indifferent to the presence of humans. They do not seem to have any fear of people; some even seek them out for attention. Some like to have their heads patted, others enjoy having their necks scratched where they meet their plastron.
Life Span
Large tortoises are among the longest-lived animals on the planet. Some individual Aldabra Giant Tortoises are thought to be over 100 years of age, but this is difficult to verify because they tend to outlive their human observers.
Conservation
The Aldabra Giant Tortoise has an unusually long history of organized conservation. No less a figure than Charles Darwin worked with the government of Mauritius to establish a preserve at the end of the 19th century.
Issue #224 -
Green-veined White
The Green-veined White (Pieris napi) is a well-known European butterfly, found in open country and woodlands.
Green-veined White, Pieris napi
Like other "white" butterflies, the sexes differ. The female has two spots on each forewing, the male only one.
Although its caterpillars feeds on crucifers, it normally selects wild species, and is therefore not the pest that some other white butterflies have become.
It can produce up to three broods in a year. Recent research has shown that when males mate with a female, they inject methyl salicylate along with their sperm. The smell of this compound repels other males, thus ensuring the first male's paternity of the eggs - a form of chemical mate guarding.
Issue #225 -
Bluefish
Bluefish (Pomatomus saltatrix) are marine fish found in all oceans except for the eastern Pacific. They are the sole members of the Pomatomidae family.
Bluefish, Pomatomus saltatrix
They have a grayish-blue coloration on the top part of the body, and a silvery coloration on the belly. They can grow to about 130 cm and can weigh up to 15 kg (31 3/4 lb). They have a reputation for being voracious predators, often eating squid and small fishes. There have been reports of bluefish eating until they regurgitate the contents of their stomachs, only to keep feeding until there are no prey remaining. Humans have been attacked by schools of bluefish in rare instances.
On the western side of the Atlantic, their range is from Argentina to Nova Scotia.
Bluefish lay eggs, the larvae of which become zooplankton and are largely at the mercy of the currents. In the western Atlantic, there are at least two populations, separated by Cape Hatteras in North Carolina. The Gulf Stream can carry larvae spawned to the south of Cape Hatteras to the north, and eddies can spin off, carrying the larvae into populations found off the coast of the Mid-Atlantic, and the New England states.
Bluefish are an important recreational fishery and are prized for their fighting ability. Their flesh is considered to be quite oily and fishy in taste.
Taxonomically, the gnomefish were formerly in Pomatomidae, but they are now in a separate family Scombropidae.
Issue #226 -
Sydney funnel-web spider
The Sydney funnel-web spider, also called a funnel-web tarantula, Atrax robustus, is regarded by some to be the most dangerous spider in the world. Actually there are two related genera of very dangerous spiders, Hadronyche (which has the higher mortality rate) and Atrax (which has produced a higher number of serious bites).
Male Sydney funnel-web spider, Atrax robustus
Examination of bite records seems to indicate that wandering males have caused a large majority of fatal bites to humans. The female venom seems to be only about a sixth as potent to humans as that of the male. The venom is known to cause death within a period ranging from one hour to three days. There have been 26 deaths in Australia in the last 100 years from spider bites, 13 of these potentially from male venomous funnel-web spiders. Most victims will have been the young, ill and infirm before antivenom was developed in 1981 through a passionate team effort led by Dr Struan Keith Sutherland (b.17 June 1936 d. 11 Jan 2002) head of immunology at the Australian Commmonwealth Serum Laboratories in Sydney. Fortunately, the antivenom is highly effective and there have been no deaths since it has been available.
Although extremely toxic to primates, the venom of the venomous funnel-web spiders appears to be fairly harmless to many other mammals, including cats and dogs. 90% of bites to humans from this spider are judged not serious enough to warrant administration of antivenom. However, the remaining 10% of the bites demonstrate the importance of promptly securing medical advice in case emergency treatment should prove necessary.
These spiders construct a funnel shaped web and lurk for prey in the small end of the funnel. They frequently search for a place to nest under human dwellings, or under nearby rocks, logs, or other similar objects. They are most active at night. They are not extremely large, the largest being about 40 mm long, but they often bite aggressively and repeatedly and may envenomate enthusiastically. Most bites seem to occur when the male spiders wander about looking for receptive female of their kind for mating during the warmer months of the year. Male spiders are often found in swimming pools, yards, and garages.
It is said that these spiders are unable to climb well because of their body weight. However they can move quickly across the ground.
Although they are rather small compared to the true tarantulas, they should not be handled without taking substantial precautions because their fangs have been known to penetrate fingernails and soft shoes, resulting in dangerous bites.
Issue #227 -
Stephen's Island Wren
The Stephen's Island Wren (Xenicus lyalli) is famous for being considered the only known species to be entirely wiped out by a single individual. The bird was a flightless, nocturnal native of Stephen's Island, New Zealand and fed on insects. It was only seen alive by Westerners on two occasions before the entire population was killed by the lighthouse keeper's cat named Tibbles in 1894. It is the most well-known of the extremely few (5 or less) flightless passerines known to exist in historic times, all of which were inhabitants of islands and are now extinct. The others were 2 or 3 relatives of Xenicus and the Long-legged Bunting from Tenerife.
Stephen's Island Wren, Xenicus lyalli
Archeological work has revealed, however, that Xenicus lyalli was widespread on the main islands of New Zealand in earlier times. Its disappearance from there was probably due to predation by the kiore (Polynesian Rat, Rattus exulans) which was introduced by the Mâori.
Conservation status: Extinct (1894)
Issue #228 -
Chartreux
The Chartreux is an internationally-recognized breed of domestic cat. Chartreux cats are from France, reportedly originally bred by Carthusian Catholic monks at their monastery in Grenoble for the purposes of catching mice to preserve food storages from loss and damage. Legend has it the Chartreux's ancestors were feral mountain cats from what is now Syria, brought back to France by returning Crusaders in the 13th century, many of whom entered the Carthusian monastic order. The first documented mention of the breed was by the French naturalist Buffon in the 17th century. The first Chartreux were brought to the USA in 1971.
Chartreux
Physically, the Chartreux is large and muscular with short but powerful limbs, big paws and very fast reflexes. They are known for their blue (grey) double-thickness fur coats and gold- or copper-colored eyes. Chartreux cats are known for their "smile"; due to the structure of their heads and long, tapered muzzle, they often appear to be smiling.
Chartreux cats tend to be quiet, rarely making noises such as mewing or crying. Some are mute. They are quite observant and intelligent, with some Chartreux learning to operate radio on/off buttons and to open screen door latches. Chartreux cats are also fond of chasing and playing well into their adult years; some can be taught to fetch small objects in the same manner as a dog. Chartreux are good with children and other animals, are nonaggressive and affectionate, good travelers and are generally very healthy.
Historically famous Chartreux owners include the French novelist Colette and French general/president Charles de Gaulle.
The Chartreux breed was advanced to championship status in 1987 by the Cat Fancier's Association (CFA.)
Country of origin: France
Issue #229 -
Aardvark
The Aardvark (Orycteropus afer) is a medium-sized mammal native to Africa. The name comes from the Afrikaans for "earth pig" (aarde earth, vark pig), because early settlers from Europe thought it resembled a pig (although Aardvarks are not closely related to pigs).
Aardvark, Orycteropus afer
The Aardvark is the only surviving member of the family Orycteropodidae and of the order Tubulidentata. The Aardvark was originally placed in the same genus as the South American anteaters because of superficial similarities which, it is now known, are the result of convergent evolution, not common ancestry. (For the same reason, Aardvarks bear a striking first-glance resemblance to the marsupial bilbies and bandicoots of Australasia, which are not placental mammals at all.)
The oldest known Tubulidentata fossils have been found in Kenya and date to the early Miocene. Although the relationships of Tubulidentata are unknown, they are probably Ungulates. They spread to Europe and southern Asia during the later Miocene and early Pliocene periods. Three genera of the family Orycteropodidae are known: Leptorycteropus, Myorycteropus, and Orycteropus, the surviving Aardvark. A genus from Madagascar may be related to them, called Plesiorycteropus.
The most distinctive characteristic of the Tubulidentata is (as the name implies) their teeth which, instead of having a pulp cavity, have lots of thin tubes of dentine, each containing pulp and held together by cementum. The teeth have no enamel coating and are worn away and regrow continuously. Aardvarks are born with conventional incisors and canines at the front of the jaw, but these fall out and are not replaced. In adult Aardvarks, the only teeth are the molars at the back of the jaw.
Aardvarks are only vaguely pig-like; the body is stout with an arched back; the limbs are of moderate length. The front feet have lost the pollex (or 'thumb')—resulting in four toes—but the rear feet have all five toes. Each toe bears a large, robust nail which is somewhat flattened and shovel-like, and appears to be intermediate between a claw and a hoof. The ears are disproportionately long and the tail very thick at the base with a gradual taper. The greatly elongated head is set on a short thick neck, and at the end of the snout is a disk in which the nostrils open. The mouth is typical of species that feed on termites: small and tubular. Aardvarks have long, thin, protrusible tongues and elaborate structures supporting a keen sense of smell.
Weight is typically between 40 and 65 kg; length is usually between 1 and 1.3 m. Aardvarks are a pale yellowish gray in color, often stained reddish-brown by soil. The coat is thin and the animal's primary protection is its tough skin; Aardvarks have been known to sleep in a recently excavated ant nest, so well does it protect them.
In the past, several individual species of Aardvark were named, however current knowledge indicates that there is only one species, Orycteropus afer, with several subspecies; 18 have been listed but most are regarded as invalid.
Aardvarks are nocturnal and solitary creatures that feed almost exclusively on ants and termites. An Aardvark emerges from its burrow in the late afternoon or shortly after sunset, and forages over a considerable home range, swinging its long nose from side to side to pick up the scent of food. When a concentration of ants or termites is found, the Aardvark digs into it with its powerful front legs, keeping its long ears upright to listen for predators, and takes up an astonishing number of insects with its long, sticky tongue—as many as 50,000 in one night has been recorded. They are exceptionally fast diggers, but otherwise move rather slowly.
Aside from digging out ants and termites, aardvarks also excavate burrows to live in: temporary sites scattered around the home range as refuges, and the main burrow which is used for breeding. Main burrows can be deep and extensive, have several entrances, and be 13 m long. Aardvarks change the layout of their home burrow regularly, and from time to time move on and make a new one. Only mothers and young share burrows.
After a gestation period of 7 months, a single young weighing around 2 kg is born, and is able to leave the burrow to accompany its mother after only two weeks. At six months of age it is digging its own burrows, but it will often remain with the mother until the next mating season. Aardvarks live for up to 10 years in captivity.
Aardvarks are distributed across most of sub-Saharan Africa, and although killed by humans both for their flesh and for their teeth (which are used as decorations), do not appear to be threatened.
The aardvark is a distant cousin of the giraffe. Aardvark is always the first noun in the English Dictionary.
Conservation status: Lower risk
Issue #230 -
European Scops Owl
The European Scops Owl (Otus scops), also known as the Eurasian Scops Owl or just Scops Owl, is a small owl. This species is a part of the larger grouping of owls known as typical owls, Strigidae, which contains most species of owl. The other grouping is the barn owls, Tytonidae.
European Scops Owl, Otus scops
This bird breeds in southern Europe eastwards into western and central Asia. It is migratory, wintering in southernmost Europe and sub-Saharan Africa. It is rare any distance north of its breeding range, usually occurring as a spring overshoot. It is unlikely that this nocturnal owl would be found outside the breeding season when it is not calling.
It breeds in open woodland, parks and gardens. It lays 3-6 eggs in a tree hole. This is a small owl, and at 19-21 cm length and a 47-54 cm wingspan is not as large as the Little Owl. It takes small prey such as insects and other invertebrates. It is largely nocturnal.
The Scops Owl perches upright and shows small ear tufts. It is predominantly grey-brown in colour, with paler face, underparts and shoulder line. This species has a strong direct flight on long narrow wings, reflecting its migratory habits.
The call is a deep whistle given by both sexes. It is similar to the call of the Midwife Toad.
Conservation status: Lower risk (lc)
Issue #231 -
King Cobra
The King Cobra (Ophiophagus hannah) is a large venomous snake of the family Elapidae. It is the only member of the genus Ophiophagus.
The King Cobra is the largest venomous snake in the world. It can reach a length of up to 5.5 metres (18 ft.), although around 3.5 metres (11.5 ft.) is more common; and can weigh up to 10 kilograms (22 pounds). The skin is black, greenish or brown, often with white or yellow bars; while the snake is young these lines are more distinct. It is a native of South-east Asia, inhabiting the forests of India, Malaysia and the Philippines, but not Sri Lanka. Its main diet is other snakes, but if it is desperate it will hunt for other small vertebrates. It only hunts during the day, by sight, and thus is classified as diurnal. As it lacks cutting teeth, it swallows its prey whole as is usual with snakes.
King Cobra, Ophiophagus hannah
The King Cobra is one of the few snakes that builds a nest and lays eggs and sits there until just before they hatch. The female makes its nest by taking dead bamboo leaves on the ground and scooping them up with her large body. Though many people say that there is nothing more aggressive than a mother King Cobra protecting her nest, it is an old wives' tale, and with a little coaxing it will leave the nest site. It lays somewhere between 20 and 40 eggs in the spring, two months after mating; the eggs hatch within 60 to 80 days. The hatchlings are between 45 and 50 centimetres long, and marked with black and white banding, and have lethal venom already. Since King Cobras are natural snake eaters, instinct causes the mother King Cobra to leave the young before they hatch, so as to prevent her from eating them, mainly because the adult has not eaten for two months. The King Cobra male is similarly unique in that it guards the nest until the young hatch, patrolling a large area around the nest for threats.
Though it is called a cobra, it is in a different genus. The scientific name Ophiophagus is derived from the Greek for "snake-eater". Though King Cobras are widely spread throughout India and southern Asia, there are no known subspecies;
The King Cobra has one of the longest lifespans among snakes (20 years). It is noted for its outstanding intelligence compared to that of other cobra species and other snakes in general. They also have excellent vision making it an expert hunter.
Drop for drop the King Cobra's venom is less lethal than many snakes including black mamba and common cobra, but the volume (7 ml) per bite is so overwhelming it can kill even an elephant or 20-30 humans. Currently anti-venom for its bite is not available readily. Its venom is a neurotoxin. It can stand in an upright threatening posture with its hood as high as 6 feet and even move in an upright stance; it can stare a human in the eye.
Adult King Cobras have no natural predators, though mongooses are known to attack young ones and steal eggs. However the greatest threat has been from human encroachment and the resultant habitat loss has resulted in dwindling numbers of this majestic snake.
Issue #232
