Wed, 20 Feb 2019
Tags: F&W / Wildlife

CWD: Challenging, Worrying and Deadly – by Brian Harris

CWD-map

It could be the plot for a science fiction horror movie. A disease that reduces the brain to Swiss cheese, spreads insidiously, is always fatal, and is caused by something that is difficult to kill because it is not actually alive. Yikes! This is Chronic Wasting Disease (CWD). It is a disease of cervids (animals in the deer family), and in Canada in the wild, it has been identified most commonly in mule deer, but also in white-tailed deer, elk and moose. Recently CWD has been reported in wild reindeer in Scandinavia, so our caribou populations are also potentially at risk.

CWD is one of a group of diseases called Transmissible Spongiform Encephalopathy that affect the brain and nervous system of many animals including humans, cattle and sheep. The disease agent is most likely an abnormal form of protein called a prion (the acronym for proteinaceous infectious particle only). Why a protein becomes a prion is not known. Proteins are normal organic molecules of healthy cells in all living creatures. However, in an animal with CWD, contact with prions causes normal proteins to change shape, then go rogue and become deadly. These altered proteins so resemble normal ones that they are not destroyed by the animal’s immune system. In certain areas of the brain, the accumulation of these abnormal proteins kills cells, so that that part of the brain looks “spongy”. As the disease progresses, body functions associated with those areas of the brain begin to fail. An affected animal gradually loses weight, becomes listless, may salivate heavily and urinate frequently. The animal eventually wastes away (hence the disease name) and dies. However, the prions in excreted body fluids and feces (and some body parts once the animal dies) may persist in the soil and be taken up by growing plants. This is a unique feature of CWD. Then, healthy animals that eat such vegetation can become infected. Even transporting feed or hay grown on land where CWD has been present can spread the disease.

CWD is well established on game farms and in wild deer in much of central USA. In Canada, so far the disease is reported only in Alberta and Saskatchewan in farmed and wild deer and elk, but in 2018, CWD was recognized on a red deer farm in Quebec. The CWD Alliance website is a good source for more information.

Monitoring for CWD in BC began in 2001 and fortunately no samples have tested positive. This is partially attributable to Provincial regulations that prohibit the farming of native cervids or importing live cervids. Recent additional regulations prohibit the importing CWD risky body parts of deer harvested outside the Province, and possessing scents derived from cervids. However, there is no room for complaisance. The Alberta CWD Program has mapped the disease expanding slowly but relentlessly westward, especially following the valleys of the South Saskatchewan, Battle and Bow Rivers. In 2017, CWD cases were reported very near to both Calgary and Edmonton. In addition, recent cases in Montana mean that BC is becoming surrounded by a growing risk of CWD.

From CWD Alliance

Some of BC’s most cherished game animals are at risk, but the disease does not affect all animals equally. In Alberta, it is mule deer that are most susceptible, while in other jurisdictions it is white-tailed deer or elk. In 2017, the Alberta Government tested for CWD in 6,340 wild deer and elk. The disease was detected in 8.2% of mule deer, 1.8% of white-tailed deer and 0.4% of elk samples (so far the only recorded incidence in Alberta moose is a single positive in 2012). Males are more likely to be infected than females. Since 2005, CWD has been detected in 796 Alberta mule deer, 119 white-tailed deer, two elk and one moose. To obtain these samples, the Alberta Government CWD Surveillance Program “relies heavily on participation by hunters, guides and landowners”.

In BC, the increasing proximity of the disease to the Province’s eastern border and the low number of samples from the Peace Region (7B) has increased the urgency for improved monitoring. In 2018, the Habitat Conservation Trust Foundation (HCTF) and partners contributed funding to improve CWD surveillance in the Peace. Most of the HCTF funding comes from the surcharge on hunting, fishing, trapping and guide outfitting licences sold in BC. This money is used to fund conservation projects benefitting wildlife and fish populations, beyond the basic management by governments.

BC’s Wildlife Veterinarian, Dr. Helen Schwantje, said, “The Peace is considered the Region at highest risk of natural expansion of CWD from Alberta into British Columbia and hunters have a key role in helping to avoid this disease from entering our Province”.

An objective of the HCTF-funded project is to increase by 10 times the number of samples from Peace Region from less than 30 to at least 300 annually. To test for CWD, the whole head of the suspect animal is required. One of the best ways to gather such samples is to involve hunters.

“Hunters are probably the group that should be the most concerned about the spread of CWD ”, says CWD Project coordinator Brian Paterson, “And coincidentally, they are the group that can help the most with early detection efforts by submitting the heads of harvested animals to our program.” Paterson continues, “As outreach coordinator, it is my role to spread information, increase awareness, and let hunters know how important the submission of a single head is in the fight against CWD.”

In 2018, Paterson delivered information on CWD to hunters in the Peace Region through contact with sportsmen’s groups, outdoor sports equipment stores, trappers, meat cutters as well as interviews on CBC and via social media sites like Facebook.

In the first year, Paterson says the response to the project has been really good, but he wants to continue the outreach and recruitment, so that “Submission of heads becomes part of the hunt. If you know that your buddies are submitting heads, you are more likely to do the same. The program can’t be truly effective without hunter participation”.

Awareness and cooperation are key, but with a sample as large as a whole head, getting to a collection site (such as dedicated freezers) must also be convenient. The locations of collection sites and a summary of the results of CWD testing will be posted on the BC Wildlife Health CWD website (www.gov.bc.ca/chronicwastingdisease.ca). If any samples test positive, the hunter will be contacted directly and confidentially.

To date, there is no treatment for affected wild animals and no vaccine, so prevention is key. The risk to BC’s game animals is real and the consequences potentially dire, but hopefully the science fiction plot of CWD does not play out in this Province. Our best defence is vigilance, and cooperation between wildlife agencies, First Nation and local governments, stakeholders and the communities most likely to be affected.

Hunters Note. Although CWD is not known to affect humans, the meat should not be eaten. Suspect animals or carcasses should be reported to the BC Wildlife Health Program (250 751-3219 or the RAPP line 1-877-952-8277). When processing a suspect animal, hunters should take care to avoid direct contact with the animal’s body fluids and especially the brain, backbone or internal organs. Avoid sawing through any bones by separating the carcass at the joints. Leave the high-risk body parts behind.

Wed, 20 Feb 2019
Tags: F&W / Wildlife

Supporting the Survival of Marten in an Era of Intensifying Fires, Climate Change and Other Pressures

American Marten
photo T. Gage

In the context of record forest fires, climate change and growing development pressure, a research project funded through a partnership between Habitat Conservation Trust Foundation and the Forest Enhancement Society of BC is exploring how American marten interact with landscapes altered by fire and salvage logging.

Logan Volkmann is pursuing a PhD under the supervision of Dr. Karen Hodges at the University of British Columbia Okanagan. For the past two years, he has been overseeing parallel American marten field projects; one is in the Okanogan National Forest in northern Washington and the other is being pursued on the Chilcotin Military Reserve near Williams Lake, BC.

As Volkmann explains, the new normal of more frequent and intense forest fires makes understanding how to better balance wildlife and harvest interests more important than ever.

“We know that we are going to have a fiery future and that will have a big impact on the species that depend on forests, including American marten,” he says. “The related question is, how does this inform how we manage landscapes, both before and after they’re burned?”

“From both a science and industry perspective, marten are an important indicator species because they are so dependent on forests. A lot of policy makers look at marten when setting new guidelines, including the timber industry. Because not a lot is currently known about how marten respond to the impact of wildfires, they are a really great species to consider when drafting new policy.”

After a forest fire, it is common practice for the timber industry to pursue salvage logging. Even after very intense fires, only the bark and foliage are burned off on many trees – the core wood is still marketable. However, as Volkmann points out, “there is still a lot of guesswork, for both scientists and industry, in terms of what landscape we want to leave after fire. How much should we log and how much should we leave? There are a lot of unanswered questions and I’m hoping that my work gets at least some of them answered.”

“Large fires are inherently very patchy. After a fire, there will be areas that are severely burned as well as areas with residual live trees. We’re finding that marten are making use of the residual patches of live trees. In terms of salvage logging, our initial observations suggest that it’s critical to leave some remnants of dead standing trees for marten habitat. Areas where lots of trees have been removed tend to be very open and we aren’t finding marten there. This observation is similar to what we already know about how marten respond to regular timber harvest. You don’t want to make your cuts too big, and you need to leave a little bit of clutter and residual structure.”

The research project is being pursued under the supervision of Dr. Karen Hodges, who has overseen multiple ongoing and recent HCTF-funded conservation science projects, including a current MSc project by Angelina Kelly, who is exploring how small mammals are using the post-fire landscape in the Williams Lake region. Both projects enjoy the support and interest of local industry, First Nations, government and trappers.

The project has been running since the winter of 2016. Volkmann has overseen two winter field seasons and one summer season; in 2017, summer fieldwork was impossible due to active forest fires.

In winter field season, a typical day starts with a 30 minute snowmobile ride. Depending on the weather, the team will either run a survey for marten tracks, or find and follow marten trails. They record GPS data from these trails to capture how the animals move through the landscape, and use that data to inform vegetation surveys during the summer field season. Starting in 2017, the team has also deployed remote wildlife cameras.

Data gathered from this project will also shed light on how other carnivores are using the landscape and adjusting to post-fire conditions. “It’s a different story for every species, depending on how strongly they need forest structure,” says Volkmann. “Species like weasels and coyotes are comfortable in more open habitat so we’re finding they are making use of salvage logged areas more than species like lynx, who are very dependent on forests.”

Staff from British Columbia’s Ministry of Forests, Lands, Natural Resource Operations and Rural Development (FLNRORD) have also been a great source of support.“FLNRORD staff have been kind enough to provide a lot of the GIS data that we need for analyzing how marten use the landscape. They provide all the mapping data in terms of forest fire size and severity. They also give us leads on local resources – where to go for housing, who to talk to for snow mobile repairs. Having never worked in Williams Lake before, they were wonderful in terms of connecting us to the local network,” says Volkmann. In particular, he says, Becky Cadsand and Carole Mahood provided key support.

Another source of expertise has been Larry Davis, a wildlife biologist conducting HCTF-supported research on fishers in the same region. “He has been extremely helpful, in terms of getting us equipment and providing local knowledge on where we should be looking for marten,” says Volkmann.

Volkmann says that it’s vital to remember that the uncertainty associated with climate change affects wildlife as well as humans, “More than ever, wildlife are contending with a landscape that’s broken up with roads and cities. As their landscapes change, they will have a harder time moving to new suitable areas. That means that understanding how animals perceive and move across landscapes, and how they respond to landscape change, is going to be more important than ever.”

HCTF is grateful for researchers like Mr. Volkmann and Dr. Hodges as well as the generous community of local conservationists, who are working together to help inform long-term decision-making to support the people and wildlife who rely on BC forests.

 

Tue, 19 Feb 2019

Lake Aeration in B.C. – Another Tool in the Toolbox – by Brian Chan

Horseshoe-lake-in-Roche-Lake-Provincial-Park-with-aeration-unit-operating-mid-winter
Horseshoe lake in Roche Lake Provincial Park with aeration unit operating mid-winter

British Columbia is blessed with an abundance of freshwater resources. Over 16,000 lakes alone are found scattered throughout the province. Our lakes offer some incredible fishing opportunities, and those located in the interior regions of the province are often glowingly referred to by anglers in the know as the best blue ribbon trout fisheries found anywhere in North America.

The backbone of our lake fisheries are those which provincial fisheries managers refer to as small lakes. They include those that are less than 2200 acres in surface area and with the vast majority being less than 220 acres. Furthermore, stocked small lakes play a huge role in creating and sustaining angling effort in the province. Approximately 800 lakes are stocked annually by the Freshwater Fisheries Society of BC. Analysis of long term angler effort data reveals that stocked small lakes support over 50% of the total annual freshwater fishing effort in the province.

So why are small lakes such an attraction for anglers? Much of their popularity comes down to where they’re located. The interior regions of the province from the Okanagan through to the Peace River are richly endowed with productive or nutrient-rich lakes. Many of these waterbodies were created several thousand years ago when the last of the glaciers receded, leaving behind scoured-out depressions that filled with water. Their shallow nature and fertile basins combined with a long, hot growing season proved to be the perfect combination for growing trout. There are also a number of nutrient rich lakes that are found on Vancouver Island and the surrounding Gulf Islands that have been managed for recreational trout fishing for decades.

Ecologically, many of these nutrient rich small lakes are classified as being in a eutrophic state. These lakes are typically shallow, with maximum depths of less than 50 ft and average depths of less than 15 ft. They are often landlocked or have only intermittent or seasonal stream connections. Because they are rich in nutrients, they are abundant in aquatic plants and invertebrates. Eutrophic lakes can be extremely productive and have the capability to grow trout and char very quickly and to large sizes. However, the same features that make accelerated growth possible in the summer can make it difficult for trout to survive over winter. Some of our most popular interior trout lakes are marginal in terms of their ability to support trout through the colder months due to a drop in dissolved oxygen levels Thousands of small trout lakes in BC’s interior freeze over for 4 to 6 months each winter. During that ice-covered period, the aquatic plants that grew through the open water seasons die off from lack of sunlight. Dissolved oxygen in the water is used up as this plant matter decomposes. As winter progresses, the volume of oxygenated water decreases to levels that become too low to support trout life, which results in a winterkill.

There are also small lakes located in the coastal regions that suffer from severe oxygen depletion during the summer months. This affects the ability of trout to survive as well as having impacts on the quality of the water for domestic use and other forms of aquatic recreation.

Lake aeration and artificial circulation is a tool that allows fisheries managers to improve over-winter trout survival in interior lakes susceptible to winterkill and provide summer refugia in eutrophic coastal lakes. In order to understand how aeration works, one needs to be aware of the seasonal changes that occur in a small lake, and how thermal stratification affects where trout can live in those waterbodies at various times of the year.

Eutrophic lakes undergo complete mixing, also known as turnover, in the spring and fall. In the spring, the lake mixes when surface temperatures become similar to that of the deeper water. Several days of wind will completely mix the entire water column, the end result being a lake fully charged with oxygen.

As summer progresses, warm air temperatures heat up the upper layers of lake water, but the energy of the sun can only penetrate so deep: beyond that depth, the water remains cold. The upper layer of warm water is referred to as the epilimnion, and the colder, deeper water is the hypolimnion. The transition zone that separates the epilimnion from the hypolimnion is known as the thermocline. The thermocline acts as an invisible barrier to the mixing of the two layers, leading to steadily decreasing levels of dissolved oxygen in deeper waters and an overall reduction in water quality.

In the late fall, as surface temperatures cool down to match the temperature of deeper water, eutrophic lakes will mix again. Brisk winds circulate the entire water column and result in the entire lake becoming well oxygenated and ready for winter.

History of Lake Aeration in B.C.

Lake aeration and artificial circulation projects were first developed in the early 1960s to address winter oxygen concerns on a number of lakes in the Okanagan and Thompson/Nicola regions. Electric or diesel powered air compressors were used to deliver oxygen through an airline and diffuser system placed in the deep part of the lake basin. Referred to as de-stratification systems, the constant stream of air bubbles created an upwelling circulation that brought deeper water to the surface where it was exposed to the air/water interface. Limited oxygen absorption into the water occurred with the release of the diffused air as well as at the lake surface.

The cost to operate and maintain these diesel and electric units proved to be very high, so other aeration/mixing systems were tested during the 1970s. Wind and solar-powered aeration units provided inconsistent results and were not well-suited to the cold, interior winter climate. It became clear that a reliable source of power was needed to successfully operate any aeration or circulation system. In the 1980s, small electric-powered floating aeration units were tried on numerous small interior lakes. These units consisted of a sealed, submersible electric motor equipped with a small propeller. They were positioned on a wooden float, and the unit suspended just below the surface of the lake. The unit pulled water from the surrounding area up to the surface along with spraying of water into the air where oxygen transfer and mixing occurred. These systems were less expensive to operate and simpler to maintain than previous models and are still used in many BC lakes today. They are typically turned on after fall turnover and then operated through the winter months. Anglers fishing aerated lakes will be familiar with the orange safety fencing that is placed at a distance around the open water surrounding the operating aerator. This fencing and accompanying signage is placed to keep anglers and other recreationalists at a safe distance from any potential thin ice.

Hypolimnetic Aeration

At the same time that electric-powered aerators were being placed in BC’s interior lakes, specific lakes on southern Vancouver Island and Salt Spring Island were being assessed for aeration suitability. These lakes were undergoing cultural eutrophication from rapidly increasing agricultural and residential development within their watersheds. Summer algal blooms, deteriorating potable water quality, and oxygen depletion concerned both fisheries and water management agencies.

An appropriate aeration system could sustain angling opportunities while improving water quality for domestic use and other forms of aquatic recreation. The first hypolimnetic aeration units were installed on Long Lake near Nanaimo, and on St. Mary’s Lake on Salt Spring Island. These were huge units requiring helicopters to lift them in place. They consisted of two large galvanized steel tubes attached to a floating box or separator raft. The tubes hung straight down and extended to the deeper parts of the hypolimnion. A diffuser with air stones was situated in the very bottom end of the intake tube, and a hose system supplied a steady stream of air to the diffuser by way of an electrical compressor. The air bubbles rising up the intake tube would create a current of water pushing to the top of the tube and then flowing down the exit tube, which was situated next to the intake tube within the separator box. This continuous circulation of aerated water resulted in marked increases in the oxygen content within the hypolimnion, while at the same time not affecting or breaking through the thermocline. The result was improved deep water fish habitat as well as reduced blue-green algal blooms which were the cause of poor water taste and quality.

Role of the Habitat Conservation Trust Foundation in Lake Aeration

Lake aeration systems were proving to be effective for both increasing winter and summer survival of trout as well as improving water quality. Unfortunately, the high cost to build, install and operate these systems meant the provincial Ministry of Environment could not continue to expand the program. It was then that the Habitat Conservation Trust Foundation (HCTF) stepped up to the plate. HCTF began in 1981 as an initiative of anglers, hunters, trappers and guide-outfitters who were willing to pay more for their licence fees if this additional funding was used to enhance fish and wildlife populations and to acquire important fish and wildlife habitat. To date HCTF has invested over $700,000 in the installation of aeration systems and provided more than $3 million dollars for the operation and maintenance of these units. The provincial lake aeration program is just one of the many habitat improvement projects that would not exist without the financial support of the Habitat Conservation Trust Foundation and licenced anglers in BC.

The Current State of Lake Aeration in B.C.

Currently, there are 20 aerated lakes across 5 different regions of the province. 4 of these are hypolimnetic systems (similar to St. Mary’s Lake), and the remaining 16 are the surface mounted de-stratification style units. Annual operation of these systems helps to sustain recreational fishing opportunities that would not otherwise be available.

For example, Red Lake located NW of Kamloops is a very popular rainbow and brook trout fishery that, prior to the installation of a hypolimnetic aeration system, would winterkill on a regular basis. Today, there are approximately 8000 angler days per year spent on this lake, with about half of that effort occurring during the winter months. This hypolimnetic aeration unit uses the latest technology which includes removing nitrogen from the air being pumped into the diffuser tube which results in close to 100% oxygen versus normal air which contains 23% oxygen. The end result is increased oxygen transfer into the water column. These hypolimnetic units also have the benefit of not creating open ice on frozen lakes. While these units are still often fenced off with safety netting, the liability concerns are significantly reduced. Simon lake is located in the southern Cariboo region just north of the town of 100 Mile House. Simon is an extremely productive waterbody that is managed for quality fishing. A surface mounted aeration unit operate through the late fall and winter months to sustain fish that reach in excess of 10 lbs. The opportunity to catch a trophy sized rainbow attracts over 1000 angler days a year to this small lake.

Other aeration projects have not been as successful. St. Mary’s Lake received the first hypolimnetic systems back in the early 1980s. It operated adequately for a number of years, but when the original unit was replaced with a larger system, the results were not as expected, and the system was eventually shut down.

Aeration is not a magic bullet to solve all fish survival and water quality issues in eutrophic lakes. It is one tool in the tool box that fisheries managers can consider for specific water bodies when conditions are right.

Brian Chan has been fortunate enough to live and work for the past 35 years in Kamloops, British Columbia. It is here that Brian, as a provincial fisheries biologist, managed the recreational stillwater trout fisheries in the Thompson/Nicola Region, and developed his fishing skills. Brian’s lifelong passion for fly fishing has resulted in his spending literally thousands of angling days on these world class waters. He has shared his extensive knowledge of aquatic biology, trout ecology, entomology, and lake fly fishing tactics with others, through magazine articles, books, and instructional DVDs. Brian has been featured on many TV fishing shows and is currently a regular guest on Sport Fishing on the Fly and co-host of The New Fly Fisher.

Thu, 14 Feb 2019
Tags: Wildlife

Feel the love today!

Haida and Pup
Oli Gardner for https://marmots.org/

Featuring Vancouver Island marmot mama Haida and her pup (possibly Muffin). Haida was born in 2002 and was one of the first released from Mountain View Conservation Centre. Despite the challenges of learning to survive in the wild, Haida went on to produce her first litter in 2006. One of those pups was Muffin. Now 12 years old, Muffin still lives at Haley Lake. She is currently hibernating with marmot Alan, and we are hoping that the pair produce a litter of pups this summer! Haida passed away a few years ago, but her loving legacy lives on.

HCTF continues to fund grants in support of the conservation of this endangered species <3

Wed, 6 Feb 2019

WANTED: Reports of dead bats and of bats flying during winter

Hibernating Little Brown Bats - Al Hicks

Pubic help needed to monitor for bat disease

BC bats are threatened by disease, and researchers are again asking for the public to help. White Nose Syndrome (WNS), a fungal disease responsible for the death of millions of bats in eastern North America, has moved to the west coast.

Confirmed in Washington State just 150 km south of the BC-US border, the presence of the fungus is very worrisome for the health of our bat populations. The disease has near 100% mortality for some species of bats exposed to the fungus, including the familiar Little Brown Myotis. Although devastating for bats, WNS does not affect humans.

The BC Community Bat Program in collaboration with the BC government is requesting the public’s help in monitoring the spread of this disease. “We believe that our bats hibernate in relatively small groups across the province” says Mandy Kellner. “Detecting WNS in our province will require many eyes on the ground”. The typical first sign of this disease is bats flying during the winter, an unusual sighting at a time of year when bats should be hibernating. Another sign of the presence of WNS is the appearance of dead bats outdoors as they succumb to the effects of WNS.

“We are encouraging the public to report dead bats or any sightings of winter bat activity to the Community Bat Project (CBP) toll-free phone number, website, or email below. Bat carcasses will be submitted for testing for White Nose Syndrome and would provide the earliest indication of the presence of the disease in BC” says Kellner. Reports of winter bat activity will help focus research, monitoring and protection efforts.

If you find a dead bat, report it to the CBP (1-855-922-2287 ext 24 or info@bcbats.ca) as soon as possible for further information. Never touch a dead bat with your bare hands. Please note that if you or your pet has been in direct contact with the bat you will need further information regarding the risk of rabies to you and your pet.

Currently there are no treatments for White Nose Syndrome. However, mitigating other threats to bat populations and preserving and restoring bat habitat may provide bat populations with the resilience to rebound. This is where the BC Community Bat Program and the general public can help.

Funded by the Habitat Conservation Trust Foundation, the Forest Enhancement Society of BC, the Province of BC, and the Habitat Stewardship Program, the BC Community Bat Program works with the government and others on public outreach activities, public reports of roosting bats in buildings, and our citizen-science bat monitoring program.

To contact the BC Community Bat Program, see www.bcbats.ca, email info@bcbats.ca or call 1-855-922-2287 ext. 24.

HCTF is providing funding for the BC Community Bat Program through grants to project 0-476, Got Bats? B.C. Community Outreach, Conservation and Citizen Science Project

Tue, 5 Feb 2019
Tags: Stewardship

Enhanced farmland benefits farmers and fowl!

Snow-Cackling-Geese-Grazing-sm
Snow & Cackling Geese grazing on winter cover crop in Richmond.

HCTF grant recipients Delta Farmland and Wildlife Trust have been working with farming operations on the Fraser River delta to enhance farmland with winter cover crops of cereal grasses, forage grasses, clovers and legume mixtures. Not only does this enrich the fertility of the soil, it also provides much needed fuel for migrating waterfowl passing through the delta.

“This project directly supports Delta and Richmond farmers committed to land stewardship. These 18 farmers have established over 2,850 acres of winter cover crops on farmland for the 2018 project year.” says Program Manager Drew Bondar.