Prey species must be Vigilant

by Dave Hanks

The world contains both predator and prey. Prey species do not live very long by being careless! Predators come in all sizes and shapes, and they must eat too. Because their prey is alert to them, they usually only make a kill after many tries. Therefore, they must use deception, speed, or make many attempts to satisfy their hunger.

Prey species may gather in large groups and depend on the many eyes, ears, and noses to alert the group to danger. Some depend on disguise to not be noticed. I don’t know how many times I would never have seen an animal, if it had not panicked, and remained motionless. Remaining in disguise is, also, a predator trick that lets the victim come close enough to surprise. Heavy bodied snakes are labeled as “Lay in wait snakes”. They can be so well concealed, that they simply latch onto a meal as it passes close by. Another interesting tactic is to look dangerous. By mimicking a poisonous species, or by looking scary (like butterflies with large eye-like spots on their wings) will deter many attacks.

Some fish simply make friends with bigger fish. By offering their services to pick parasites off the host’s back, or to clean their teeth; makes the smaller fish more valuable for its service than it would be as a meal. The predator protects them because they are far more useful alive than dead.

Muskrats are the epitome of wariness. They are most difficult to photograph, even though you may be aware of their presence. They rely on well camouflaged, safe havens. Their speed of swimming, while keeping a low profile in the water, lets them escape to burrows excavated in the banks of slow moving streams. These burrows are well hidden amid the stream’s sedges. The dens have many underwater tunnels leading to several dry chambers that have ventilation holes. Here the animal can bring in food, or wait out any perceived dangerous situation.

A Muskrat caught unawares

A Muskrat caught unawares

The Deer Mouse: Food for Many

by Dave Hanks

You have probably seen a Coyote stalking along in the tall grass, pausing, and then leaping skyward in an exaggerated pounce. The canine is catching rodents and Deer Mice are among the most plentiful. This white-bellied, white-pawed, and white-tailed mouse is eaten by owls, hawks, snakes, and other small meat eaters. The mouse does not hibernate and a Great Horned Owl can hear the mouse running under the snow and correctly gage where to pounce to make the kill.

Because it is preyed upon so heavily, reproduction at a rapid rate is essential.The female mouse will produce up to seven litters or more when feeding conditions are favorable. Her gestation lasts from 21 to 24 days and she comes back into estrus immediately (postpartum) upon giving birth. You could say that she is continually pregnant. The nest is a hollow ball of grass on the ground, and the new born in it are hairless, wrinkled, pink, and with their eyes not opened. The mother will transport the young to new locations, either in her mouth, or by the babies clinging to her nipples.

Deer Mice are poor climbers and so their life is spent on the ground where they dine on seeds and insects. They especially prefer weedy or tall grassy areas and the resulting seeds and cover. There is a danger that can come to humans from contact with this mouse’s droppings. They may contain a deadly virus which causes HPS (Hantavirus Pulmonary Syndrome).

There are over 100 sub-species of this rodent. Their white-colored undersides will differentiate them from the mouse we are most familiar with – the House Mouse. Deer Mice are nocturnal. The one pictured alerted us to its presence – we could hear it chewing away just outside our camper door.

A Deer Mouse gnawing on our birdseed in the middle of the night

A Deer Mouse gnawing on our birdseed in the middle of the night

Long-Tailed Weasel: Feared Predator of the Lesser World

What has one of the most powerful bites for its size in the predator world? What has a small head and tube-like body that can go down most burrows? What predator is a greatly feared hunter, in the rodent world in which it hunts? What animal must kill around 500 rodents a year to satisfy its upkeep? It’s the Long-Tailed Weasel.

Voles (commonly known as field mice) are its “ice cream species” (that is the food an animal prefers above all else). However, larger prey will be taken when voles are not available. They will eat the head and thorax first and any leftovers are stored in the burrow. Weasels do not hibernate and so they will kill more than they can consume. This is added to their larder for times when prey is scarce.

This weasel is brown above and yellowish below and in northern climes turns white in winter, except for its tail tip which remains black. Males are twice as heavy as females. Its cousin, the Short-Tailed Weasel (or Ermine) has a white belly and is slightly smaller. Weasels are Mustelids (like skunks) and have scent glands that produce a strong odor for marking territory, defense, and most often used during the mating season. They also have well defined whiskers, which are quite sensitive and useful for navigation in darkness or in secluded places. They can swim or climb trees when necessary.

The Long-Tailed Weasel is the most wide-spread carnivore in the western hemisphere. The habitats they frequent always have water close at hand. We have experienced them in Waterton Provincial Park in Alberta and at Lake Cleveland – where we often see them “slithering’ out of the rocks and then quickly disappearing.

This small, elongated predator is retiring, but can be very aggressive if confronted.

A young weasel  at the water

Young weasel at the water