All rights reserved. Wiggins Revision: M. Wyndham, Photo: Robert McCaw. The Northern Leopard Frog Lithobates pipiens is named for its leopard-like spots across its back and sides. Historically, these frogs were harvested for food frog legs and are still used today for dissection practice in biology class.
Northern Leopard Frogs are about the size of a plum, ranging from 7 to 12 centimetres. They have a variety of unique colour morphs, or genetic colour variations. They can be different shades of green and brown with rounded black spots across its back and legs and can even appear with no spots at all known as a burnsi morph.
They have white bellies and two light coloured dorsal back ridges. Another pale line travels underneath the nostril, eye and tympanum, ending at the shoulder. The tympanum is an external hearing structure just behind and below the eye that looks like a small disk. Black pupils and golden irises make up their eyes. They are often confused with Pickerel Frogs Lithobates palustris ; whose spots are more squared then rounded and have a yellowish underbelly. Male frogs are typically smaller than the females.
Their average life span is two to four years in the wild, but up to nine years in captivity. Tadpoles are dark brown with tan tails. Lampreys are an amazing group of ancient fish species which first appeared around million years ago. This means they evolved millions of years before the dinosaurs roamed the earth. There are about 39 species of lamprey currently described plus some additional landlocked populations and varieties. In general, lamprey are one of three different life history types and are a combination of non-parasitic and parasitic species.
Non-parasitic lamprey feed on organic material and detritus in the water column. Parasitic lamprey attach to other fish species to feed on their blood and tissues. Most, 22 of the 39 species, are non-parasitic and spend their entire lives in freshwater. The remainder are either parasitic spending their whole life in freshwater or, parasitic and anadromous. Anadromous parasitic lampreys grow in freshwater before migrating to the sea where they feed parasitically and then migrate back to freshwater to spawn.
The Cowichan Lake lamprey Entosphenus macrostomus is a freshwater parasitic lamprey species. It has a worm or eel-like shape with two distinct dorsal fins and a small tail. It is a slender fish reaching a maximum length of about mm. When they are getting ready to spawn they shrink in length and their dorsal fins overlap. Unlike many other fish species, when lampreys are getting ready to spawn you can tell the difference between males and females.
Females develop fleshy folds on either side of their cloaca and an upturned tail. The males have a downturned tail and no fleshy folds. These seven gill pores are located one after another behind the eye. There are several characteristics which are normally used to identify lamprey.
Many of these are based on morphometrics or measurements, of or between various body parts like width of the eye or, distance between the eye and the snout. Other identifying characteristics include body colour and the number and type of teeth. Some distinguishing characteristics of this species are the large mouth, called and oral disc and a large eye.
This species also has unique dentition. For example, these teeth are called inner laterals. Each lateral tooth has cusps and together they always occur in a cusp pattern. At the same time, the Sea Otter is the largest member of its family, the mustelids, which includes River Otters, weasels, badgers, wolverines and martens.
It may come to land to flee from predators if needed, but the rest of its time is spent in the ocean. It varies in colour from rust to black. Unlike seals and sea lions, the Sea Otter has little body fat to help it survive in the cold ocean water.
Instead, it has both guard hairs and a warm undercoat that trap bubbles of air to help insulate it. The otter is often seen at the surface grooming; in fact, it is pushing air to the roots of its fur. Mollusks are invertebrates, meaning they have no bones. They are cold-blooded, like all invertebrates, and have blue, copper-based blood. The octopus is soft-bodied, but it has a very small shell made of two plates in its head and a powerful, parrot-like beak. The Giant Pacific Octopus is the largest species of octopus in the world.
Specimens have weighed as much as kg and measured 9. Studies determined, though, that they are indeed different.
While the Western Chorus Frog might have slightly shorter legs than the Boreal Chorus Frog, and that their respective calls have different structures, genetics have proven this.
Chorus Frogs are about the size of large grape, about 2. They are pear-shaped, with a large body compared to their pointed snout. Their smooth although a bit granular skin varies in colour from green-grey to brownish. They are two of our smallest frogs, but best ways to tell them apart from other frogs is by the three dark stripes down their backs, which can be broken into blotches, by their white upper lip, and by the dark line that runs through each eye.
Their belly is generally yellow-white to light green. Males are slightly smaller than females, but the surest way to tell sexes apart is by the fact that only males call and can inflate their yellow vocal sacs.
Adults tend to live only for one year, but some have lived as many as three years. Their tadpoles the life stage between the egg and the adult are grey or brown. Their body is round with a clear tail. The Common Raven Corvus corax is one of the heaviest passerine birds and the largest of all the songbirds.
It is easily recognizable because of its size between 54 and 67 centimetres long, with a wingspan of to cm, and weighing between 0. It has a ruff of feathers on the throat, which are called 'hackles', and a wide, robust bill. When in flight, it has a wedge-shaped tail, with longer feathers in the middle.
While females may be a bit smaller, both sexes are very similar. The size of an adult raven may also vary according to its habitat, as subspecies from colder areas are often larger.
A raven may live up to 21 years in the wild, making it one of the species with the longest lifespan in all passerine birds. Both birds are from the same genus order of passerine birds, corvid family —like jays, magpies and nutcrackers, Corvus genus and have a similar colouring. But the American Crow is smaller with a wingspan of about 75 cm and has a fan-shaped tail when in flight with no longer feathers.
Their cries are different: the raven produces a low croaking sound, while the crow has a higher pitched cawing cry. While adult ravens tend to live alone or in pairs, crows are more often observed in larger groups. The Atlantic Cod Gadus morhua is a medium to large saltwater fish: generally averaging two to three kilograms in weight and about 65 to centimetres in length, the largest cod on record weighed about kg and was more than cm long!
Individuals living closer to shore tend to be smaller than their offshore relatives, but male and female cod are not different in size, wherever they live.
The Atlantic Cod shares some of its physical features with the two other species of its genus, or group of species, named Gadus. The Pacific Cod and Alaska Pollock also have three rounded dorsal fins and two anal fins. They also have small pelvic fins right under their gills, and barbels or whiskers on their chins. Both Pacific and Atlantic Cod have a white line on each side of their bodies from the gills to their tails, or pectoral fins. This line is actually a sensory organ that helps fish detect vibrations in the water.
The colour of an Atlantic Cod is often darker on its top than on its belly, which is silver, white or cream-coloured. In rocky areas, a cod may be a darker brown colour.
Cod are often mottled, or have a lot of darker blotches or spots. It can weigh up to 63, kilograms and measure up to 16 metres. Females tend to be a bit larger than males — measuring, on average, one metre longer.
Its head makes up about a fourth of its body length, and its mouth is characterized by its arched, or highly curved, jaw.
Its skin is otherwise smooth and black, but some individuals have white patches on their bellies and chin. It has large, triangular flippers, or pectoral fins. Its tail, also called flukes or caudal fins, is broad six m wide from tip to tip! Unlike most other large whales, it has no dorsal fin. For a variety of reasons, including its rarity, scientists know very little about this rather large animal. For example, there is little data on the longevity of Right Whales, but photo identification on living whales and the analysis of ear bones and eyes on dead individuals can be used to estimate age.
It is believed that they live at least 70 years, maybe even over years, since closely related species can live as long. Unique characteristics. The Right Whale has a bit of an unusual name. Its name in French is more straightforward; baleine noire, the black whale. The American Eel Anguilla rostrata is a fascinating migratory fish with a very complex life cycle. Like salmon, it lives both in freshwater and saltwater. It is born in saltwater and migrating to freshwater to grow and mature before returning to saltwater to spawn and die.
The American Eel can live as long as 50 years. It is a long, slender fish that can grow longer than one metre in length and 7. Males tend to be smaller than females, reaching a size of about 0. With its small pectoral fins right behind its gills, absence of pelvic fins, long dorsal and ventral fins and the thin coat of mucus on its tiny scales, the adult eel slightly resembles a slimy snake but are in fact true fish.
Adult eels vary in coloration, from olive green and brown to greenish-yellow, with a light gray or white belly. Females are lighter in colour than males. Large females turn dark grey or silver when they mature.
The American Eel is the only representative of its genus or group of related species in North America, but it does have a close relative which shares the same spawning area: the European Eel.
Both have similar lifecycles but different distributions in freshwater systems except in Iceland, where both and hybrids of both species can be found. The American Lobster Homarus americanus is a marine invertebrate which inhabits our Atlantic coastal waters. As an invertebrate, it lacks bones, but it does have an external shell, or exoskeleton, making it an arthropod like spiders and insects.
Its body is divided in two parts: the cephalothorax its head and body and its abdomen, or tail. On its head, the lobster has eyes that are very sensitive to movement and light, which help it to spot predators and prey, but are unable to see colours and clear images.
It also has three pairs of antennae, a large one and two smaller ones, which are its main sensory organs and act a bit like our nose and fingers. Around its mouth are small appendages called maxillipeds and mandibles which help direct food to the mouth and chew. Lobsters have ten legs, making them decapod ten-legged crustaceans, a group to which shrimp and crabs also belong other arthropods have a different number of legs, like spiders, which have eight, and insects, which have six.
Four pairs of these legs are used mainly to walk and are called pereiopods. The remaining pair, at the front of the cephalothorax, are called chelipeds and each of those limbs ends with a claw. These claws help the lobster defend itself, but also capture and consume its prey.
Each claw serves a different purpose: the bigger, blunter one is used for crushing, and the smaller one with sharper edges, for cutting. The Barn Swallow Hirundo rustica is a medium-sized songbird, about the size of a sparrow.
It measures between 15 and 18 centimeters cm in length and 29 to 32 cm in wingspan, and weighs between 15 and 20 grams g. Its back and tail plumage is a distinctive steely, iridescent blue, with light brown or rust belly and a chestnut-coloured throat and forehead.
Arriving females select a cavity, essentially inheriting the male associated with that cavity Johnston and Hardy Purple Martins are a single-brooded species, second broods are rare Brown Arrivals typically continue at individual colonies for weeks Hill Timing of arrival is age and sex-related, as older age classes generally precede younger birds, and males generally precede females of their respective age class.
In Texas, second-year Purple Martins arrive about two months after the earliest birds arrive Brown When new colonies are established, it is usually by these late-arriving second-year birds Hill The clutch of eggs is laid on a pad-like nest of coarse materials, lined with green leaves. Often, the nest contains a mud dike, which is constructed at the cavity entrance and slopes downward toward the rear of the cavity.
The incubation period is sixteen days, and the young receive care in the cavity for days. Upon fledging, the young are kept together, and fed for an additional weeks.
Soon after fledging, premigratory aggregations form, and most Purple Martins have left the state by the end of September Ray The birds tend to avoid birdhouses placed near trees or shrubs and, in fact, will likely abandoned houses if trees or shrubs encroach on them Hill a,b. A nearby water source is not a prerequisite for having Purple Martins, but they seem to be most numerous around water, and will travel several kilometers to drink, bathe, and capitalize on the abundance of flying insects normally found around water Ray Installation of martin houses has allowed for a range expansion westward into northwest Texas in recent years Ray In the absence of management see Ray , nest site competition and reduced productivity caused by House Sparrows Passer domesticus and European Starlings Sturnus vulgaris represent the biggest threat to nesting Purple Martins Brown , Hill Short-term regional declines usually result from weather-related mortality Peterjohn and Sauer Brown, C.
The impacts of starlings on Purple Martin populations in unmanaged colonies. Purple Martin Progne subis. The Dawnsong is a vocalization sung by adult males in the early morning hours to attract other martins to their colony site. Dawn singing coincides with adult egg-laying and lasts until the migration of subadults has ended.
It can be heard for many miles during the pre-dawn hours and is a very effective attraction technique. Although it is rarely seen between bonded, paired birds, it is sometimes seen as forced or extra-pair copulations among martins that are not paired up for the breeding season.
It is believed that copulation between pairs occurs in the nest cavities. Egg laying commences after copulation occurs.
Females lay one egg per day, usually in the morning, for a total of two to seven pure white eggs. After the penultimate, or next to last, egg is laid, females begin incubation.
Only females can incubate eggs because only they have a brood patch, a featherless area rich in blood vessels that transfers heat to the eggs.
Males may insulate the eggs for short periods of time while the female leaves the nest. Fifteen to sixteen days later, the eggs begin to hatch. The eggs may not hatch on the same day, but rather it can be spread out over two or even three days.
Once the young have hatched, both parents begin feeding the young. Pin feathers and downy feathers begin to emerge after days. Fledging occurs days after hatching.
The young receive care from their parents for one to two weeks after fledging. During this time, the young may return to their housing to spend the night. After fledging, juvenile Purple Martins, as well as adults and subadults will congregate at a roost.
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