An Animal A Day

last SG · 2005-03-09T00:11:15+00:00

Deepwater Arrowtooth Eel The Deepwater Arrowtooth Eel (Histiobranchus bathybius) is a cutthroat eel of the genus Histiobranchus, found around the world at d...

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Komodo Dragon

The Komodo Dragon (Varanus komodoensis) is the largest lizard in the world, growing to a length of 3 metres and weighing between 80 and 140 kg (175 to 310 lb). It is a member of the monitor lizard family, Varanidae.

Komodo Dragon, Varanus komodoensis

Dragons have keen senses and are considered among the most intelligent living reptiles.

They are carnivores and hunt live prey, with a stealthy approach followed by a sudden short charge (they can run briefly at speeds up to 20 km/h). They have a strong bite augmented by severe infection of wounds, caused by the some 50 different strains of bacteria in their saliva. After they bite, they release their prey to allow it to die before devouring it; this allows them to avoid injury. Dragons will fight over kills.

Dragons eat any animals they can catch, up to the size of wild pigs, goats, deer, and water buffaloes and occasionally including human beings. Over a dozen human deaths have been attributed to dragon bites in the last century, though there are reports of survivors of the resulting septicemia.

Mating occurs between May and August, with the eggs laid in September. The eggs are protected, but the hatchlings (100 g and 40 cm in length) are not and most are eaten. Komodo Dragons take around five years to grow to 2 metres in length and can live for up to 30 years.

There are around 6,000 living Komodo Dragons, restricted to the Lesser Sunda Islands in Indonesia, including the islands of Komodo (1,700), Rinca (1,300), Gili Motang (100) and Flores (maybe 2,000).

The Komodo monitor was first reported by a European in 1910. The creatures were introduced to the rest of the world in a 1912 paper by Peter Ouwens, the director of the Zoological Museum at Bogor, Java.

In order to protect the Komodo Dragon, in 1980 the Komodo National Park was founded.

Two komodo dragons at a komodo ranger station.

Conservation status: Vulnerable

Issue #14

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Fire Salamander

The Fire Salamander (Salamandra salamandra) is probably the most well-known salamander species in Europe. It is black with yellow spots or stripes to a varying degree - some specimens can be nearly completely black while on others the yellow is dominant. In some cases the spots are more orange or red than yellow.

Fire Salamander, Salamandra salamandra

Habitat

Fire salamanders live in forests in the hilly parts of southern and central Europe. They prefer deciduous forests, as they like to hide in the fallen leaves, but also at mossy tree trunks. They need clean small brooks in their habitat for the development of the larvae.

Fire salamanders are active in the evening and the night, but on rainy days they are active in daytime as well. Their diet consists of various insects, spiders, earthworms and slugs.

Reproduction

Males and females look much alike except during the the breeding season, when the most conspicuous difference is a swollen gland around the male's vent. This gland produces the spermatophore, which carries a sperm packet at its tip. The courtship happens on land. After the male becomes aware of a potential mate, he captures her and blocks her paths. The male now deposits his spermatophore on the ground. Reproduction occurs by means of this spermatophore, which will be taken up by the female salamander.

The eggs are retained in the oviducts of females by developing within several months. Under normal conditions the females give ovoviviparous birth to nearly full developed aquatic larvae with external gills and caudal fin borders. After several months, the larvae transform into adults and leave the water. During the transformation they lose their gills and develop lungs. Neotenic fire salamanders were watched at no time.

Larva with external gills

Toxicity

Fire salamanders are able to extrude heavy toxic skin secretions, e.g. the neurotoxic alkaloid Samandarin. This alkaloid causing to all vertebrates strong muscle convulsions and high-blood pressure combined with hyperventilation. The poison glands of salamanders are concentrated in certain areas of the body, especially around the head and the dorsal skin surface. Most of these secretions might be effective against bacterial and fungal infections of the epidermis, but some secretions can also be dangerous to human life.

The neurotoxic alkaloid Samandarin produced in the skin glands of the Fire Salamander.

Distribution

Fire salamanders are found in most of southern and central Europe. They are most commonly found at altitudes between 400 and 1000 m, only rarely below. However on the Balkan or in Spain they are commonly found in higher altitudes as well.

Map of Europe showing the distribution of the Fire Salamander.

Names of the fire salamander across Europe:

-- England - Fire salamander, Spotted salamander
-- France - Salamandre tachetée
-- Spain - Salamandra commún
-- Italy - Salamandra pezzata
-- Netherlands - Vuurslamander
-- Norway - Ildsalamander

Subspecies

Several subspecies of the Fire salamander are recognized. Most notable are the subspecies fastuosa and bernadezi, which are the only viviparous subspecies - the others are ovoviviparous.

-- S. s. almanzoris - Spotted Fire Salamander
-- S. s. bejarae (or hispanica)
-- S. s. bernardezi (extinct?)
-- S. s. beschkovi
-- S. s. crespoi
-- S. s. fastuosa (or bonalli) - Yellow Striped Fire Salamander
-- S. s. gallaica - Portuguese Fire Salamander
-- S. s. gigliolii
-- S. s. infraimmaculata
-- S. s. longirostris - Los Barrios Fire Salamander
-- S. s. morenica
-- S. s. salamandra (or werneri)
-- S. s. semenovi
-- S. s. terrestris - Barred Fire Salamander

Issue #15

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Carolina mantis

The Carolina mantis or mantid (Stagomantis carolina) is the state insect of South Carolina. It is also called a praying mantis. This is but one of many species of Mantodea (genus Stagomantis). The Carolina Mantis is the smallest of the three types native to North America. It can grow up to 7.6 cm or about 3 inches in length. In the South it is known as rearhorse or mulekiller.

Carolina mantis, Stagomantis carolina

The Carolina Mantis has a dusty brown or gray color used to camouflage with the pine forests and sand hills of the Southeastern part of the United States. A distinguishing trait is that its wings only extend three quarters of the way down the abdomen.

It is sometimes kept as a pet, as a large, easily cultured insect. It also, unlike most insects, will turn its head to watch a person or an insect that it is attempting to catch.

It is a voracious predator, capturing many insects in the course of its life, and occasionally it will capture and eat an anole (a type of lizard) or even a hummingbird.

Close-up picture of the mantis head.

Carolina mantis egg cases (called an ootheca singularly) can be purchased in garden supply centers as a means of biological control of pest insects.

Issue #16

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Neon tetra

The neon tetra (Paracheirodon innesi) is a freshwater fish of the characin family (family Characidae) of order Characiformes. The type species of its genus, it is native to blackwater or clearwater streams in South America, in particular the tributaries of the Solimões.

Neon tetra, Paracheirodon innesi

The neon tetra is light in color, apart for the characteristic Paracheirodon iridescent blue-green horizontal stripe along each side of the fish from nose to the front part of the tail and its prominent red coloration along the posterior half of the lower body. It grows to approximately 3 cm (1.25 in) in overall length. Sexual dimorphism is slight, the female having a slightly larger belly.

P. innesi is one of the most popular aquarium fish, having been bred in tremendous numbers for the trade.

The green and black neon tetras are distinct species (the latter belonging to an altogether different genus, in fact) and not color varieties. The cardinal tetra, also sometimes called the red neon, is a very similar species and is often confused with the true neon tetra. Hyphessobrycon innesi, on the other hand, is an obsolete synonym for P. innesi, the neon tetra itself.

In the aquarium

Neon tetras are considered easy to keep in a community aquarium. They tend to be timid unless hungry, and because of their small size they should not be kept with large or aggressive fish, who may bully or simply eat them. Mid-level feeders, they are best kept in schools of five to eight or more, for the "shoaling" effect when they move around the tank. Their color and the iridescent stripe may become dim at night, and they can be virtually invisible after a period of darkness.

While neon tetras bred commercially have adapted to a wide range of water conditions, in the wild they inhabit very soft, slightly acidic waters, between 20 and 26 °C (6879 °F).

Issue #17

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Brittle star

Brittle stars are echinoderms, closely related to starfish. They crawl across the sea-floor using their flexible arms as "legs" for locomotion and lack the tube feet possessed by the true starfish or asteroids. The ophiuroids generally have five long slender, whip-like arms which may reach up to 60 centimeters (2 feet) in length on the largest specimens.

A brittle star on a sponge

Ophiuroidea contains two large clades, the Ophiurida (brittle stars) and Euryalida (basket stars). Many of the ophiuroids are rarely encountered in the relatively shallow depths normally visited by humans, but they are a diverse group.

There are some 1,500 species of brittle stars living today, and they are largely found in deep waters more than 500 metres (1,650 feet) down.

Range/ Location

Ophiuroids can be found in all of the major marine provinces, from the poles to the tropics. In fact, crinoids, holothurians, and ophiuroids rule the floor of the deep oceans at depths below 500 metres. Basket stars usually confined to the deeper parts of this range. Ophiuroids are known even from abyssal (> 6000m) depths. However brittle stars are also common, if cryptic, members of reef communities, where they hide under rocks and even within other living organisms. A few ophiuroid species can even tolerate brackish water, an ability otherwise almost unknown among echinoderms.

The ophiuroids diverged in the Early Ordovician, roughly 500 million years ago. Their fossil record is weak, since brittle stars (as their name implies) tend to break apart easily.

Fossil brittle star Palaeocoma egertoni from the Jurassic of England

Disk and internal organs

Like all echinoderms, the Ophiuroidea possess a calcium carbonate (calcite) skeleton. In ophiuroids, the calcite ossicles are fused to form armor plates (collectively, the test).

Of all echinoderms, the Ophiuroidea may have the strongest tendency toward 5-segment radial (pentaradial) symmetry. The body outline is similar to the Asteroidea, in that ophiuroids have five arms joined to a central disk (calyx). However the central body disk in ophiuroids is sharply marked off from the arms. The disk contains all of the viscera. That is, the internal organs of digestion and reproduction never enter the arms (in contrast to Asteroidea).

The mouth is rimmed with five jaws. Behind the jaws is a short esophagus and a large, blind stomach cavity which occupies much of the dorsal half of the disk. Ophiuroids have neither an intestine nor an anus. Digestion occurs within 10 pouches or infolds of the stomach. Gas exchange and excretion occur through cilia-lined sacs called bursae; each opens onto the interambulacral area (between the arm bases) of the oral (ventral) surface of the disc. Typically there are 10 bursae, and each fits between two stomach digestive pouches.

The sexes are separate in most species. Gonads in the disc open into the bursae. Gametes are then shed by way of the bursal sacs. Many species actually brood developing larvae in the bursae. The ophiuroid coelom is strongly reduced, particularly in comparison to other echinoderms. The nervous system consists of a main nerve ring which runs around the central disk. At the base of each arm, the ring attaches to a radial nerve which runs to the end of the limb. Ophiuroids have no eyes, as such. However, they have some ability to sense light through receptors in the epidermis.

Both the Ophiurida and Euryalida have five long, slender, flexible whip-like arms, up to 60 cm in length. They are supported by an internal skeleton of calcium carbonate plates that referred to as vertebral ossicles. These "vertebrae" articulate through ball-in-socket joints, and are controlled by muscles as shown in the figure. The body and arms are also bear calcite plates and delicate spines. Euryalids are similar, if larger, but their arms are forked and branched. Ophiuroid podia generally function as sensory organs. They are not usually used for feeding, as in Asteroidea.

The vessels of the water vascular system end in tube feet. The water vascular system generally has one madreporite. However, some forms have none. Suckers and ampullae are absent from the tube feet.

Ophiuroids can readily regenerate lost arms or arm segments unless all arms are lost. Ophiuroids use this ability to escape predators, like lizards who automize, or deliberately shed, part of their tails to confuse pursuers.

Locomotion

Brittle stars use their arms for locomotion. They do not, like starfishes, depend on tube feet. Brittle stars move fairly rapidly by wriggling their arms which are highly flexible and enable the animals to make either snake-like or rowing movements.

Trophic

Many ophiuroids are scavengers or detritivores. Small organic particles are moved into the mouth by the tube feet. Ophiuroids may also prey on small crustaceans or worms. Basket stars, in particular may be capable of suspension feeding, using their mucous covering the branched arms to trap plankton and bacteria.

Issue #18

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Moa

The moa were giant flightless birds of New Zealand. Ten species are known, of varying sizes, with the largest species, the Giant Moa (Dinornis robustus and Dinornis novaezelandiae), reaching about three metres (ten feet) in height and about 250 kilograms (550 pounds) in mass. They were the dominant herbivores in the forest ecosystem.

Moa became extinct around the year 1500. This is thought to be due to hunting and land clearance after humans arrived in the islands although another school of thought suggests that numbers were declining before the impact of humans. Before the arrival of humans, some moa were hunted by Harpagornis, the world's largest eagle which is also now extinct. The kiwi are regarded as moderately close relatives of the moa.

Although the indigenous Maori told European settlers tales about the huge birds which they called Moa, which had once roamed the flats and valleys, the widespread physical evidence that they had actually existed was never closely examined by early European settlers.

In 1839, John W. Harris, a Poverty Bay flax trader who was a natural history enthusiast, was given a piece of unusual bone by a Maori who had found it in a river bank. He showed the 15cm fragment of bone to his uncle, John Rule, a Sydney surgeon, who sent it to Richard Owen who at that time was working at the Hunterian Museum at the Royal Colllege of Surgeons in London. Owen became a noted biologist, anatomist and paleontologist at the British Museum.

Sir Richard Owen and Dinornis skeleton from The Book of Knowledge, The Grolier Society, 1911

Owen puzzled over the fragment for almost four years. He established it was part of the femur of a big animal, but it was uncharacteristically light and honeycombed.

Owen announced to a skeptical scientific community and the world that it was from a giant extinct bird like an ostrich, and named it "Dinornis". His deduction was ridiculed in some quarters but was proved correct with the subsequent discoveries of considerable quantities of moa bones throughout the land, sufficient to construct skeletons of the birds.

Although dozens of species were described in the late 19th and early 20th century, many were based on partial skeletons and turned out to be synonyms. More recent research, based on DNA recovered from museum collections, suggest that there were only ten species, including two giant moa. The giant moa seems to have had sexual dimorphism, with females being much larger than males; so much bigger that they were formerly classified as separate species.

In July 2004, the Natural History Museum in London placed on display the moa bone fragment Owen had first examined, to celebrate 200 years since his birth, and in memory of Owen as founder of the museum.

Though there is no reasonable doubt that the Moa is extinct, there has been occasional speculation that some may still exist in deepest south-westland, a rugged wilderness in the South Island. Cryptozoologists and others reputedly continue to search for them, but none have ever been found, and some might regard such efforts as pseudoscience. In 1993, two people claimed to have seen a bird they suspect was a Moa, but their report was largely dismissed as a hoax.

Conservation status: Extinct (c. 1500)

Issue #19

SGpork SG

MOA ??

dontknow ... Laughing

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to know more animals, come here often < Laughing >

SGpork SG

ok

mr pct Laughing

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Airedale Terrier

The Airedale Terrier (often shortened to "Airedale") is a large and versatile terrier dog breed originating from the Aire valley in Yorkshire, England. It is often called the "King of Terriers" because it is the largest of the terrier breeds, 50 to 70 pounds (23-32 kg). The Airedale was bred originally to hunt otters. It was also called a "Waterside Terrier" because of this connection to hunting otters.

Airedale Terrier

Appearance

The Airedale coat

Like many terriers, it has a 'broken' coat, which requires regular hand stripping to maintain the coat and distinctive square terrier shape. A broken coat is a harsh, wiry topcoat with a soft, fur-like undercoat. Broken-coated breeds do not shed their coats as much as smooth coated breeds, and are therefore less likely to cause allergic reactions in people prone to dog allergies.

Stripping is the correct process for grooming an Airedale, using a small serrated edged knife to pull out loose hair from the dog's coat. Airedales who aren't being shown are often clipped with electric clippers. This process, while easier on the dog and the groomer, softens the coat and fades the color, and sometimes causes skin allegies for the dog. This is because the loose hair that would normally moult is cut, so the roots remain within the hair follicles.

The correct coat color is a black saddle, with a rich tan head, ears and legs; or a dark grizzle saddle (black mixed with gray and white). Both are acceptable in the AKC breed standard.

Tail

The Airedale's tail is usually docked (surgically shortened) within five days of birth, but this is not a requirement of breed standard authorities. However, to show an Airedale in the United States, the tail is expected to be docked.

This Airedale's tail is natural (undocked).

History of the Airedale

The Airedale was extensively used in World War One to carry messages to soldiers behind enemy lines and occupying the trenches. They were also used extensively by the Red Cross to find wounded soldiers on the battlefield. Their courage and stalwart character in the face of danger was legendary. In fact, the German designation for an Airedale is "Kriegshund" which means "War dog". Before the adoption of the German Shepherd as the dog of choice for law enforcement and search and rescue work, the Airedale terrier often filled this role.

Airedale temperament and character

The Airedale can also be used as a working dog and also as a hunter and retriever. However, he is typically an independent (stubborn), strong-minded dog with a great sense of humour. For those who can laugh along with their Airedale, patience will be rewarded as they have been known to reach great heights in competitive obedience, dog agility, and Schutzhund. He is also a reliable and protective family pet.

Health

The Airedale is relatively free of inherited diseases except for hip dysplasia in some lines. He usually lives for around twelve years, but has been know to last until the age of seventeen.

Country of origin: Great Britain (England)

Issue #20

SGpork SG

cute dog Laughing

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Przewalski's Horse

Przewalski's Horse (Equus przewalskii or E. caballus przewalskii), also known as the Mongolian Wild Horse, or Takhi, is the closest living relative of the Domestic Horse and may in fact be the same species. (Authorities differ about the correct classification.) The two are the only equids that can cross-breed and produce fertile offspring.

Przewalski's Horse, Equus przewalskii

As of 2002, the world population of these horses is about 1,000, all descended from approximately 15 captured around 1,900 and bred in zoos. The wild population in Mongolia died out in the 1960s; captive-bred horses were returned to the wild starting in 1992. The area to which they have been reintroduced became Hustai National Park in 1998. Three of these horses now graze in a 12 acre (49,000 m²) paddock in the Clocaenog Forest in North Wales, UK, on the site of a former Neolithic/Iron Age settlement. The Forestry Commission hopes they will help recreate scenes from the Iron Age when these horses first roamed free in the woods.

Przewalski's Horse is stockily built in comparison to domesticated horses, with shorter legs. Typical length is about 2.1 metres (7 feet) with a 90 cm (3 foot) tail. They weigh around 350 kilograms (770 lb). The coat varies from dark brown around the mane (which stands erect) to pale brown on the flanks and yellowish-white on the belly.

In the wild, Przewalski's Horses live in social groups consisting of a dominant male, several mares, and their offspring. Each group has a well-defined home range; within the range, the herd travels between three and six miles a day, spending time grazing, drinking, using salt licks, dozing, and taking mud baths. At night, the herd clusters and sleeps for about four hours.

Fillies leave their natal groups around age 2, and look for a herd to join, after which they will begin to breed. Colts are driven out when they are about three years old, and spend a year or two in small bachelor herds, practicing fighting. At around age 5, a stallion will try to pass on his genes by attempting to take over an existing herd, stealing one or more mares from another stallion's harem, or gathering unattached fillies.

The horse is named after General Nikolaï Mikhaïlovitch Prjevalski (18391888) who was also an explorer and naturalist.

Conservation status: Extinct in the Wild

Issue #21

starblue SG

The animal kingdom is organised into evolution trees. it goes:

Kingdom --> Superphylum --> Phylum --> Subphylum --> Superclass --> Class --> Subclass --> Order --> Family --> Genus --> Species.

so humans are:

Animialia Chordata Vertebrata Gnathostomata Mammilia Placental Carnivora Primate Homo Sapien.

what a mouth full.... Wink

SGpork SG

i want fire horse..

not this

Laughing

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Red-billed Hornbill

Hornbills are a family of tropical near-passerine birds found in the Old World.

The Red-billed Hornbill (Tockus erythrorhynchus) is a common resident breeder in much of sub-Saharan Africa. During incubation, the female lays three to six white eggs in a tree hole, which is blocked off with a cement made of mud, droppings and fruit pulp. There is only one narrow aperture, just big enough for the male to transfer food to the mother and the chicks.

Red-billed Hornbill, Tockus erythrorhynchus

When the chicks and the female are too big to fit in the nest, the mother breaks out and rebuilds the wall, then both parents feed the chicks.

This species has mainly whitish underparts and head and grey upperparts. It has a long tail and a long curved red bill which lacks a casque. Sexes are similar, but the female has a smaller bill. It is a large bird, at 42cm in length, but is one of the smaller hornbills.

This species is omnivorous, taking insects fruit and seeds. It feeds mainly on the ground and will form flocks outside the breeding season.

This conspicuous bird also advertises its presence with its noisy accelerating "tok-tok-tok-toktoktok" call.

Issue #22

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Anaconda

Anacondas are three species of aquatic boa inhabiting the swamps and rivers of the dense forests of tropical South America.

An anaconda in South America

Two species are well-known:

-- The Green Anaconda (Eunectes murinus), which has been reported at up to 10 metres in length (although most are considerably smaller). Although shorter than the longest recorded species, the Reticulated Python, it is considerably heavier. In fact, it is the heaviest snake species in existence. It can weigh 250 kg and have a girth of more than 30 cm in diameter. Females are larger than males. These are found mainly in northern South America, in Venezuela, Colombia, Brazil, northern Bolivia, northeast Peru, Guyana, and Trinidad.

-- The Yellow Anaconda (Eunectes notaeus), which reaches a relatively smaller maximum length of 3 metres. These live further south in Bolivia, Paraguay, Uruguay, western Brazil, and northeast Argentina.

The third lesser known species is:

-- The Dark-Spotted or Deschauense's Anaconda (Eunectes deschauenseei) found in northeast Brazil.

Eunectes murinus (formerly called Boa murina) differs from Boa by the snout being covered with shields instead of small scales, the inner of the three nasal shields being in contact with that of the other side. The general colour is dark olive-brown, with large oval black spots arranged in two alternating rows along the back, and with smaller white-eyed spots along the sides. The belly is whitish, spotted with black. The anaconda combines an arboreal with an aquatic life, and feeds chiefly upon birds and mammals, mostly during the night. It lies submerged in the water, with only a small part of its head above the surface, waiting for any suitable prey, or it establishes itself upon the branches of a tree which overhangs the water or the track of game.

Like almost all boas, anacondas give birth to live young.

Anacondas have a reputation for bad temperament; that plus the massive size of the green species mean that anacondas are comparatively less popular as pets than other boas.

Issue #23

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Common toad

The Common toad or European toad (Bufo bufo) is widespread throughout Europe, with the exception of Ireland and some Mediterranean islands. Its easterly range extends to Irkutsk in Siberia and its southerly range includes parts of northwestern Africa in the northern mountains of Morocco, Algeria, and Tunisia.

Common toad, Bufo bufo

Adults can grow to 18 cm (7 in) and their skin has a warty appearance and ranges from green to brown. As a defense against predators they secrete a toxic, foul tasting substance (bufagin). This is enough to deter many predators although grass snakes and hedgehogs are immune. Although the adults spend most of their time on land the females enter ponds and other still water to lay their eggs, toadspawn, which can be distinguished from the spawn of the common frog as it forms strings rather than than a large mass of eggs. Eggs are laid in the spring, with the females attempting to return to the water in which they were born. The young tadpoles resemble other tadpoles in their appearance except that toadpoles have a larger, rounder blacker head and shorter tail.

Common toads eat invertebrates such as insects, larvae, spiders, slugs and worms, which they catch on their sticky tongues. Larger toads may also take slow worms, small grass snakes and harvest mice, which are swallowed alive. Toads generally hunt at night, and are most active in wet weather.

In Great Britain many toads are killed on the roads while migrating to their breeding grounds, in some places special tunnels have been constructed so they can cross under roads and local wildlife groups run toad patrols carrying them across busy crossing points in buckets.

Toads have a long association with European witchcraft, as familiars and ingredients in potions.

Adult (female), Vitinia (Roma), Italy

Adult (male), Manziana (Roma), Italy

Issue #24

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Asian long-horned beetle

The Asian long-horned beetle (Anoplophora glabripennis) is native to China and Korea where it causes widespread mortality of poplar, willow, elm, and maple throughout vast areas of eastern Asia.

Asian long-horned beetle, Anoplophora glabripennis
The bettle is shown on a cross-section of a tree it has damaged, creates large holes that inhibit the vascular system and ultimately kill the tree.

Asian longhorned beetles are big, showy insects: shiny and coal black with white spots. Adults are about 1 inch (2.5 cm) long. On their head is a pair of very long antennae that are alternately ringed in black and white. The antennae are longer than the insect's body.

An invasive species in the United States, the larva of this beetle has a voracious appetite for wood. It is especially damaging to maple trees: Norway, sugar, silver, and red maple are among its preferred foods. The species also feeds on horse-chestnut, poplar, willow, elm, mulberry, and black locust. Females of this species chew into the bark and lay eggs. When the eggs hatch, the immature beetles, which look like big white worms, chew their way farther into the tree. When they mature, the full-grown beetles chew their way out of the tree. The beetle life cycle leaves trees riddled with holes, oozing sap. The United States Department of Agriculture (USDA) believes this beetle can probably survive and reproduce in most sections of the country where suitable host trees exist.

At the Beneficial Insects Introduction Research Laboratory in Newark, Delaware, Asian longhorned beetle larvae are maintained on cuttings made from twigs of various tree species.

Issue #25

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Atlantic herring

The Atlantic herring (Clupea harengus) is the most abundant fish species of the world, living in large schools (swarm). Growing up to 45 centimeters in length and more than half a kilogram in weight, they feed on copepods, krill and small fish and are food for seals, whales, cod and other larger fish.

Adult Atlantic herring, Clupea harengus

The Atlantic herring fishery has long been an important part of the economy of New England and the Canadian Maritime provinces, because the fish congregates relatively near the coast in massive schools, notably in the cold waters of the semi-enclosed Gulf of Maine and Gulf of St. Lawrence. North Atlantic herring schools have been measured up to 4 cubic kilometers in size, containing an estimated 4 billion fish.

Looping underwater video of a school on its migration to their spawning grounds in the Baltic. With such high speeds, they can migrate over thousands of kilometers. In the North Atlantic they cruise between Norway and Greenland every year.

A typical school of herring heads to shore during mating season, usually during the fall. Each female lays from 50,000 to 90,000 eggs, which sink to the ground and stick to it via an adhesive covering.

Schools can on calm days sometimes be detected at the surface from more than a mile distance, by the little waves they form, or from a few meters at night, when they trigger bioluminescence of surrounding plankton ("firing"). All underwater recordings show herring constantly cruising with high speeds up to 108 cm per second, and much higher escape speeds.

Slow motion macrophotography video (50% timelag, looping, each image shifted to compensate the rolling microturbulences from the waves) of feeding juvenile herring (38 mm) on copepods - the fish approach from below and catch each copepod individually. In the middle of the image a copepod escapes successfully to the left.

In this sequence a herring attacks four times in a row (50% timelag, looping, each image shifted to compensate the rolling microturbulences from the waves). In the third attack the copepod is visible between the wide opened sides of the mouth. The opercula are spread wide open to compensate the pressure wave which would alert the copepod to trigger a jump.

If prey concentrations reach very high levels, like in microlayers, at fronts or directly below the surface, herring ram forwards with wide open mouth and far expanded opercula over several feet, then closing and cleaning the gill rakers for a few milliseconds ("sift feeding" or "filter feeding").

Spawning herring. There is at least one herring stock spawning in any one month of the year, each race having a different spawning time and place (spring, summer, autumn and winter herrings) in 0 to 5 m off Greenland down to 200 m in autumn (bank) herrings of the North Sea. Eggs are laid on the sea bed, on rock, stones, gravel, sand or beds of algae. " .. the fish were darting rapidly about, and those who have opportunity to see the fish spawning in more shallow water ... state that both males and females are in constant motion, rubbing against one another and upon the bottom, apparently by pressure aiding in the discharge of the eggs and milt" (Moore at Cross Island, Maine).

Herring eggs. A female herring may deposit from 20,000 up to 40,000 eggs, according to her age and size, averaging about 30,000. In sexually mature herrings, the genital organs are so large just before spawning commences that they make up about one-fifth of the total weight of the fish.

Eggs attached to algae. The eggs sink to the bottom, where they stick in layers or clumps to gravel, seaweeds or stones, by means of their coating mucus, or to any other objects on which they chance to settle.

Freshly hatched herring larvae. The larvae are 5 to 6 mm long at hatching, with a small yolk sac that is absorbed by the time a length of 10 mm is reached. Only the eyes are well pigmented (a camera works only with a black housing) the rest of the body is as transparent as possible, and virtually invisible under water and natural luminance conditions.

The dorsal fin is formed at 15 to 17 mm, the anal fin at about 30 mm - the ventral fins are visible and the tail becomes well forked at 30 to 35 mm - at about 40 mm the little fish begins to look like a herring.

Adult herring

Issue #26

poon cho tang SG

Sea angel

Sea angels are small pteropod mollusks of the suborder Gymnosomata. Their feet have developed into wing-like appendages (parapodia) and their shells have been lost, both adaptations made to suit their free-swimming oceanic lives. These adaptations also explain the common name sea angel and the New Latin name of the order; from gymnos meaning "naked" and soma meaning "body." Within the order are approximately eight families and 17 genera.

Sea angel, Clione limacina

Also known as gymnosomes, sea angels belong to the Orthogastropoda a subclass of Gastropoda (snails and slugs) which includes nudibranchs. The other suborder of pteropods, Thecosomata, are superficially similar but not closely related. They have larger, broader parapodia, most species retaining a shell, and are known commonly as sea butterflies.

Sea angels are gelatinous, mostly transparent and very small, with the largest species (Clione limacina) reaching 5 cm. Clione limacina is a polar species; those found in warmer waters are far smaller. Some species of sea angel feed exclusively on sea butterflies; the angels have terminal mouths with the radula common to mollusks, and tentacles to grasp their prey, sometimes with suckers similar to cephalopods. Their "wings" allow sea angels to swim much faster than the larger (usually fused) wings of sea butterflies. Other species of sea angel feed mostly on zooplankton.

Another large polar species of sea angel, Clione antarctica, defends itself from predators by synthesizing a previously unknown molecule, named pteroenone. As predators will not eat the sea angel some animals, such as amphipods, take up home inside them. Local population density of Clione antarctica may reach claustrophobic levels; up to 300 animals per cubic metre have been recorded.

Slowly beating their parapodia, sea angels gracefully fly through the upper 20 metres of the water column. Although usually slow-moving, they are capable of surprising bursts of speed. The animals are simultaneous hermaphrodites, fertilization occurring internally. A gelatinous egg mass is released during spawning, the eggs floating freely until hatching. Their embryonic shells are lost within the first few days after hatching.

Issue #27

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