A tiger in your grass

by Art Jones

I share my home with five cats. Yes, count 'em, five cats. How they came to live in my house is a story for a different time.

The cats that live in my home spend most of their time indoors. When they do go outside they are kept on a leash. The leashes were originally used to keep the cats safely away from traffic and other animals. Now it turns out the leashes may have been doing the local birds and small
animals a favour.

Cats and humans have co-existed for a long time. First domesticated in Egypt around 4,000 years ago they were introduced to Europe around 2,000 years ago. Cats first arrived in North America with the European immigrants. Large numbers were imported during the late nineteenth century in an attempt to control a growing rodent population associated with
agriculture.

It's estimated there are now around five million domestic cats in Canada and those animals kill about 140 million birds and small mammals every year. A similar situation exists in Britain, New Zealand and Australia. In the United States 66 million pet cats and an estimated 40 million feral or wild cats kill a billion small mammals and hundreds of millions birds every year. Although some of those kills are mice, rats and other species seen as pests, many times a cat takes a bird or animal whose population is already under pressure from other things such as habitat loss.

A study done in Wisconsin showed cats kill more birds and small mammals than all of the foxes, skunks, raccoons and other mid-sized predators.

Rick Espie of Saskatchewan Environment says that's partly due to the fact that there are so many cats and that most cats are efficient predators.

"The populations of natural predators rises and falls with the availability of prey so when the prey population crashes, the predators go hungry and their numbers fall. That, in turn, reduces the pressure on the prey which then allows those populations to rebound," says Espie.

"That isn't the case with cats. Cats are an introduced species so their prey does not have a natural defense. On top of that, most cats are usually well fed or subsidized by food from a bowl. That means their population stays the same while the birds and small mammals they hunt are always under pressure. For domestic cats, hunting is not a matter of life and death; they kill
because they are programmed to hunt."

Many cat owners put bells on their pets thinking that will alert the birds and animals being hunted. But bells don't work because birds and animals often don't connect the sound of a bell to danger and because cats can learn to stalk without ringing the bell.

Farmers that use cats for rodent control should keep only as many animals as needed and spay and neuter all cats. Studies show spayed females stay closer to home. Some people even mount owl boxes near out buildings to attract natural predators. City people can do several things including spaying and neutering all cats, making sure bird feeders are away from places cats can hide, training cats to a leash and keeping pet cats indoors.

"Really what is at stake is the health of many of our migratory small-bird populations,' says Espie. "Cats are not responsible for the toll they take on our wildlife-people are. The only way to stop domestic cats from killing birds and animals is to keep them inside."

Keeping your cat indoors has other benefits as well. A cat that spends a lot of time outside has an average life span of two to six years, while a cat kept indoors can live fifteen or more years.
There are several websites where you can get more information. They include www.abcbirds.org ,
www.wildflorida.org/critters/domestic_cat.asp,
whyfiles.org/086urban_critter/index.html,
www.cdri.org/Discovery/Feral%20Cats.html.
www.umext.maine.edu/onlinepubs/htmpubs/7148.htm,
and
www3.simpatico.ca/samgreen/webcats.html.

For more information contact:

Rick Espie
Biodiversity Specialist
Saskatchewan Environment
(306) 787-2461
respie@serm.gov.sk.ca

Or

Art Jones
Communications Consultant
Saskatchewan Environment
(306) 787-5796
(306) 536-8452 (cell)
ajones@serm.gov.sk.ca

Trees are our breathing partners

A tree whose hungry mouth is prest Against the sweet earth's flowing breast

by Art Jones

Those are the first four lines of the poem "Trees" by Joyce Kilmer, 1886-1918. It is among the most loved and most recognized poems in North America.

It was also a tribute to the beauty and strength of trees.

Trees are something most people take for granted. They're just there, in the yard, along the streets, in clumps on the plains and in the forests in the north.

But have you ever wondered what a tree really does?

Urban trees provide shade and shelter and act as windbreaks. The water evaporating from their leaves helps to reduce the temperature near the tree reducing the need for air conditioning in nearby homes. A tree acts like a huge pump that cycles water up from the soil and into the air. In a single growing season a healthy 33-metre tree with 200,000 leaves can take approximately 40,000 litres of water from the soil and breathe it back into
the air.

A windbreak of trees can help maintain moisture levels during the summer and during the winter a windbreak can lower heating costs by nearly a third. Trees help stabilize the soil and reduce erosion and conserve water by slowing runoff after storms. Urban trees muffle noise almost as effectively as stonewalls and one study says trees around your home can increase
property values.

Trees provide homes, shelter and food for countless birds, animals and insects and have a direct impact on the health of aquatic ecosystems.

Trees play a role in more than 5,000 products, including nuts, fruit, berries, syrup, baseball bats, paper, wood, shoe polish and even toothpaste.

"I am constantly amazed by the number of things we use that come from trees," says Al Willcocks of Saskatchewan Environment. "In Saskatchewan the most economically important activities include logging and manufacturing forest products such as pulp and paper, lumber, oriented strand board, plywood and fence posts. The forest industry has an enormous economic benefit in Saskatchewan, employing nearly 8,000 people and pumping more than $884-million into the economy."

Trees also help reduce the amount of carbon dioxide going into the atmosphere. A young, rapidly growing forest takes carbon dioxide from the atmosphere, stores the carbon as biomass and releases oxygen. In an old forest the trees aren't growing any more. As the mature trees die and rot and are eaten by insects, the net effect is to release the stored carbon into the atmosphere. When there is a fire the carbon stored in the old trees is also released into the atmosphere. If some of these trees are harvested before that happens and made into something durable such as building materials or furniture, the carbon stays in the wood and out of the atmosphere.

"Because forests take carbon dioxide out of the air they are, in a sense, our breathing partners," says Environment's Willcocks. "People and animals depend on trees and plants for oxygen. As you breathe in, your body uses oxygen. As you breathe out, it gives off carbon dioxide. Trees and other plants do the opposite. They take in carbon dioxide and release oxygen into the atmosphere. It's estimated that Saskatchewan's forests produce enough oxygen for 241 million people for a year."

Environment's Willcocks says that while most people readily see the value in mature forests for forest products and recreation, it's also important to understand the critical function of young forests. All parts of the forest- like each line in a poem - must work together and balance is the key.

For more information contact:

Al Willcocks
Executive Director, Forest Services
Saskatchewan Environment
(306) 953-2468
awillcocks@serm.gov.sk..ca

Or

Art Jones
Communications Consultant
Saskatchewan Environment
(306) 787-5796
(306) 536-8452 (cell)
ajones@serm.gov.sk.ca

The spruce budworm may be small but it has a big appetite

Aerial Spraying to Combat Spruce Budworm

by Art Jones

During this summer Saskatchewan Environment will use aerial spraying to treat approximately 30,000 hectares of forestland in the Deschambault Lake and Amisk Lake areas for spruce budworm. The biological pesticide, Bacillus thuringiensis var. kurstaki (Btk), which is a naturally occurring soil bacterium and kills certain types of caterpillars, will be used.

Btk has been safely used around the world for nearly 40 years. It is not harmful to other insects such as bees, or fish, birds or wildlife and poses no human health hazard. Btk does not build up in the environment and if the target insect, the budworm, does not eat it, Btk will only survive for a few days after application.

Spruce budworm is a natural part of our forest ecosystem but high populations can pose a threat to valuable timber resources," says Saskatchewan Environment Entomologist, Rory McIntosh, "The objective of our budworm management program is to protect these resources by managing heavy infestations in selected areas while allowing the insect to play its natural
role in the ecosystem in most areas."

Spruce budworm larvae are small, only 18 to 24 millimetres long. They are greenish-brown with two rows of whitish spots along the back. However, the impact they have on the forests can be enormous.

In late June or July, the adult moth lays clusters of eggs on the needles of balsam fir, white spruce and black spruce. The eggs hatch in 10 days. The larvae find a protected spot on the tree and soon begin to spin a shelter of silk where they will spend the winter. In May, the larvae emerge and feed on old needles, unopened buds or male flowers eventually making their way into the growing shoots. They pupate in June and the cycle begins again.

"One of the reasons for concern is the budworm's messy eating habits," says Environment's McIntosh "They use their silk webbing to tie two or three shoots together to form a feeding tube. Then they bite needles off at the base. The needles dry out, leaving masses of silk and dried red-brown needles hanging from the trees. Repeated defoliation during a heavy infestation of budworms can eventually kill a tree or make it so weak it dies."

Dead trees along with the masses of dry needles and silk increases the risk of severe wildfires. If damage continues over the next few years, the risk of fires spreading to nearby commercial forests, communities and tourist operations increases.

"Fire is a natural process of regeneration in our boreal forest', says Environment's McIntosh. "However, the build-up of fuel caused by the budworm and the greater chance of wild fire means that we have to use other tools to reduce this hazard. For example, carefully planned logging allows us to reduce the fire hazard while still making use of the damaged trees."

The Provincial Spruce Budworm Management Program has been operating since 1992. Results of the program are monitored and reported. Ongoing surveys reveal that defoliation in areas treated with the biological pesticide, Btk has been reduced by as much as 60% when compared to areas that have not been sprayed.

For more information contact:

Rory McIntosh
Provincial Entomologist
Saskatchewan Environment
(306) 953-3617
rmcintosh@serm.gov.sk.ca

Or

Art Jones
Communications Consultant
Saskatchewan Environment
(306) 787-5796
(306) 536-8452 (cell)
ajones@serm.gov.sk.ca