Invasive Species Invade our Inland Waterways

The spiny water flea is an invasive species that has assaulted our inland waterways. It is amazing how such a small creature, one-quarter of an inch (1cm), can be so destructive to native species. It is a predator and a relative of the “fishhook water flea”. In 1982 they were introduced to North America in the ballast waters of European ships entering the Great Lakes. They have spread throughout the Great Lakes and to at least 60 inland lakes in Ontario.
As the name suggests the spiny water flea has a long tail spine with barb-like projections. The head has a large black eye and a pair of swimming antennae. They have a pair of mandibles, or jaws used to pierce and shred their prey. The four pairs of legs are, not for walking, but for catching and holding food while it is being consumed. The two front legs are longer than the others and are used to reach out and catch prey. The other three pairs of legs hold their prey while they eat it.
The spiny water flea preys on small, indigenous organisms called zooplankton, including Daphnia, which are important foods for native fishes. When the populations of this invader reach massive levels, zooplankton consumption can be significant. The invasive species eats about three times as much as our native species and therefore reduces the amount of food available for resident water fleas and juvenile fish.
When water conditions are ideal female spiny water fleas reproduce identical female offspring. Females produce from one to ten eggs that are able to develop into new females every two weeks. When water conditions are poor, low water temperatures or not enough food, females produce only males.
When the females mate they produce “resting eggs” which can remain dormant over long periods of time, ---over winter and even out of water for a period of time. The eggs hatch when conditions improve. The life span of a spiny water flea varies from several days to a few weeks.
The extent of the damage done to fish populations by the spiny water flea has not been clearly determined. Past experience with invasive species indicates that in almost every situation native species have come out second best.
Fish will feed on spiny water fleas but fish smaller than four inches (11cm) long have difficulty swallowing the fleas. The tail spine of the spiny water flea gets caught in the throat of the fish and is literally coughed out. This prevents the fish from getting any nourishment for its efforts.
At the present time the best defence against the spiny water flea is to prevent its transfer to new bodies of water. You should inspect and clean all fishing equipment including lines, nets, lures, boats and trailers before leaving any body of water. Drain the water from your motor, live well, bilge and transom wells. Do not release live bait into any body of water and recheck your fishing gear before every trip on the water.
Your grandchildren will thank you.
Speaking of Nature.
Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario K7V 3Z8 Phone 613-432-2738 email jamesh@nrtco.net

They are Eating our Lawns Already

There is no frost in the ground to hinder their arrival and the larva of the June bug has begun its destruction of our lawns. We will not see any adults until May but until then the white grubs which are the larva of the June bug will be feeding on the roots of our lawn grasses.
June bug, is a common name for any of several beetles in the scarab family, they are also called June beetles. Actually June bugs are not bugs at all but beetles and there are 100 North American species all of which like the underground parts of any vegetation. There are several imports from other countries as well and they are just as destructive as our native species. Some cause more devastation because they do not have any natural enemies.
The female June bug lays her eggs in the ground where they hatch within a few weeks. The larvae burrow down below the frost line for the winter and return to just below the surface for the summer months and feed on plant roots.
The larvae, known to horticulturalists as white grubs, are white, fat and C-shaped. They burrow in the soil, feed on the roots of plants and damage lawns, pastures and grain crops. The larval stage continues to develop in the ground for two or three years before emerging as an adult. It is these tender morsels that the raccoons and skunks are looking for when they dig up our lawns. I have seen squirrels and chipmunks enjoying them as well.
In summers when there is a large infestation of the grubs the skunks and raccoons will turn over large areas of sod in their search for them. It is difficult to tell which does the most damage, the grubs or the animals searching for them. I am sure we could do without both.
The large brown adult beetles are attracted to lights during May and much of June. They belong to a family of beetles that includes Tumblebugs, Dung Beetles, Rhinoceros Beetles, Hercules Beetles and Elephant Beetles; the family is large in more ways than one.
We are most familiar with the June bug, the brown one we see below our night-lights or climbing up the outside walls of our homes. The adult June bug is about one inch (25mm) in length, brown in colour and has two sets of wings. The front set is hard and used to protect the delicate hind wings, which are used for flying. When the beetle lands it folds the hind wings gently into place and then covers them with the front wings, somewhat like closing the barn doors.
The adult June bugs are just as destructive as the grubs. They feed on flowers and the foliage of various trees and shrubs and are capable of completely defoliating them. The leaves will often return but they are much smaller than the first growth. On rare occasions the leaves do not return until the following spring. Damage to the bark can also take place and other diseases will attack the trees. When these conditions occur the trees will loose lose a year’s growth or they may die.
Speaking of Nature.
Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario K7V 3Z8 Phone 432-2738 Email jamesh@nrtco.net

One Depends on the Other

Some 65 million years ago, the first bees, wasps, butterflies and moths appeared on earth. They are the insects that depend on flowers as a source of nutrition during their adult life. From that time onward flowers and certain groups of insects became dependent on one another and therefore contributed to the development of each other.
As the plants developed bright coloured flowers and called attention to the nectar and other food supplies insects developed a taste for the sweet nectar and the nutritious pollen. Prior to this the plants had grown structures that folded over one another to protect the reproductive parts of the plant from hungry pollinators. To overcome the added protection new species of wasps and bees evolved that had strong legs and mouth parts capable of opening the flowers to extract the pollen and nectar.
A flower that attracts only a few kinds of insect visitors and attracts them regularly has an advantage over flowers visited by undependable pollinators. It is an advantage for the insect to have a private food supply that is difficult to get to by insects competing for the same food.
Modern flowers have many distinctive features or special adaptations that encourage regular visits by particular pollinators. The various shapes, colours, and odors allow for sensory recognition by specific pollinators.
Flowers such as orchids, snapdragons and irises with their deep, trumpet-like blooms and unusual landing platforms exclude all but a few desired pollinators; the rest must go away hungry.
Bees pollinate flowers while they are foraging. The anthers deposit pollen grains on the bee’s mid section and when the bee moves to another flower the pollen falls off or is scraped off onto the new flower. Beetles push their way into a flower to get to the nectar or pollen and the sticky pollen clings to their head. When they move to a different flower they take the pollen with them and it brushes off as they search for more food.
The long sucking tongue of a butterfly is able to reach into the flowers of daisy to extract the nectar but in the process collect pollen to be deposited when they visit another flower. Moths are active pollinators as they make their rounds. They, like the butterflies, have long tongues and can sip nectar from deep within the flower’s petals. They collect pollen while they are feeding and spread it to other flowers as they move about.
As hummingbirds collect nectar from a lily or any deep-throated species, pollen collects on the bird’s forehead and is then deposited on the next flower the bird visits. Hummers are particularly good at their job because they will visit many flowers of the same species one after another and this makes sure each flower is pollinated.
Lately there has been a drastic reduction in the numbers of pollinators, mainly bees, and some crop growers must buy hives of bees to pollinate their crops. What is causing the decline is not fully understood which prevents a plan from being developed to solve the problem.

Speaking of Nature

Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario k7V 3Z8 Phone 613-432-2738 email jamesh@nrtco.net

Things Pike Fishermen Should Know

The northern pike spawns in the spring and spawning takes place immediately after the ice is off our lakes and rivers in early April or May. Water temperatures at this time of year range between 40 and 50 degrees Fahrenheit (4.4-11.1 degrees Celsius). The spawning run for a single female lasts about nine days reaching a peak six or seven days after the initial set of eggs. After seven days the run declines rapidly and finally ends on the ninth day. Over the period the water temperatures average about 48 degrees Fahrenheit (nine degrees Celsius).
This species generally spawns during daylight hours on heavily vegetated flood plains of rivers, marshes and bays or our larger lakes and rivers. One spawning run of 6000 mature pike was tabulated in a single creek tributary in a Northern Ontario Lake.
The sexes pair at spawning time and the larger females are usually attended by one large male or two or more smaller ones. They swim through and over the vegetation in the shallow water often not much deeper than seven or eight inches (178-190mm). At intervals the female will deposit eggs on or in the vegetation and the males will cover them with milt. A thrusting of the tail, which scatters the eggs and moves the adult fish to a new spawning area, follows each spawning act.
The spawning act is repeated many times every day over a three to five day period.
There is no nest built and the eggs are scattered at random, usually in groups of from five to sixty eggs at a time. The eggs are about one tenth of an inch (3mm) in diameter, clear, amber in colour and very adhesive. As a result they remain on the vegetation in the spawning area until they hatch.
Egg numbers as high as 595,000 have been reported and they increase with the size of the female. The weight of the eggs has been estimated at 9000 per pound. The number of eggs deposited is high, and the fertility rate is usually over 50% but the number of young that, actually survive is very low.
It has been estimated in one study that of approximately one million eggs laid only 1800 young survived to leave the spawning grounds. This represents a 99.8% mortality rate.
The status of the pike population in local lakes is not clearly known or understood. I have heard from many ardent fishermen that there are not as many fish in our waters as there once were.
There are so many factors involved that it is difficult to put the blame any one offender. Increased amounts of acid rain, ultraviolet light caused by ozone depletion, over fishing, chemical pollution, destruction of natural shorelines and natural spawning habitat all contribute in one way or another to the reduction in fish numbers.
What can we do? First be involved in a catch and release program. Do not fish illegally; the rules are made to help preserve our fish stocks. Be a conscientious conservationist when fishing. Or be like me. Go to fish but do not catch anything.
Speaking of Nature
Jim Ferguson, 5313 River Road, R.R.5, Renfrew, Ontario k7V 3Z8 Phone 613-432-2738 email jamesh@nrtco.net