Oct 112019
 

Grassland birds and aerial insectivores among the hardest hit

When I was a teenager in the 1960s, the Peterborough Field Naturalists made an annual June visit to Harry William’s farm near Millbrook. This was not your average nature outing. You were expected to arrive no later than 4:00 am. Why, you may ask? To take in the dawn chorus as the world would reawaken to a cacophony of bird song. Upon arriving, the most dominate  voices were those of the whip-poor-wills. They were deafening. In fact, as former club president, Martin Parker, recalls, “It was so loud your head throbbed.” Once the whip-poor-wills quieted down, other species began to sing. They were always right on cue, each at its own designated time. First came the thrushes, followed in order by the sparrows, the buntings, the warblers, and then field birds like meadowlarks. You were buffeted by a continual wave of sound. The challenge was trying to pick out and identify the different voices competing for airtime.

Fast forward to 2019. When you walk outside at dawn, even in wilderness areas, the relative silence is eerie. Yes, birds are still singing, but the boisterous wall of sound is gone. Parker agrees. “I find the dawn chorus at my cottage getting quieter and quieter every year.”

An alarming report

According to a study published this September in Science magazine, North America has lost nearly three billion birds over the last five decades. Take a moment to let that number sink in. Stated another way, about one-third of the total bird population we had in 1970 has disappeared. The study looked at 50 years of data gathered by volunteers who carry out annual bird censuses like the Breeding Bird Survey, provincial and state breeding bird atlases, and the Christmas Bird Count. Scientists also looked at data from 143 weather radars, which pick up the millions of birds migrating in the spring and fall through the sky. The decline was there before their very eyes. Although the drop in bird populations has been known for a long time,  the authors of the study were stunned by the scale of the loss.

This is not so much a story of extinction – although that may soon be the reality for some species – but rather the story of a “great thinning”, in which once-abundant birds have declined to a fraction of their former numbers. It should serve as a stark warning. As Ken Rosenburg, the study’s lead author said, “Birds are so interwoven with everything else (in nature) that if we’re seeing this loss and degradation in birds, we can be pretty sure it’s happening with other groups, and that it’s a symptom of a much larger problem with the environment that will ultimately affect people.”

A good case in point is the world-wide decline in insects. We need look no further than the windshields of our cars. No longer are they splattered with dead moths, butterflies and other insects like they once were. Insects, of course, sustain birds.

 The worst declines

Three bird groups in particular have taken the brunt of the downturn. Canada has lost 40 percent of its shorebirds and nearly 60 percent of its grassland and aerial insectivore populations. These groups also make up 80 percent of all bird species that have been newly assessed as threatened or endangered in Canada.

Let’s look at grassland species. These include familiar birds such as killdeers, meadowlarks and bobolinks. A grassland can be a prairie, a field that is no longer being farmed, or even a hayfield. Bobolinks, which love to nest in hayfields, have plummeted by 88 percent. One reason is that hayfields are often mowed during the breeding season, which destroys the nests. Grassland birds are also threatened by changing agricultural practices such as intensification, removal of hedgerows, and inputs of pesticides.

Along with the Renfrew area, the Kawarthas has the highest nesting densities of bobolinks in Ontario. I asked Dr. Erica Nol, professor of biology at Trent University, what could be done to help this species recover. She said, “Working with farmers to set aside hayfield reserves on their farms would be a useful strategy. The fields don’t have to be large and, of course, the farmers would need to be compensated. Many grassland species wouldn’t be here if it wasn’t for farmers.”

Aerial insectivores – birds that feed on the wing by catching flying insects – have declined by 59 percent across Canada. This group includes swallows, martins, whip-poor-wills, nighthawks, chimney swifts, and flycatchers. The precipitous drop in barn swallow numbers has been most noticeable. Any farmer over the age of 50 can attest to the large flocks of swallows that once nested in barns and lined telephone wires. Cottagers of a certain age will remember how common they were in boathouses.

We are already well aware of the negative impacts of neonicotinoid pesticides on bee populations, but now the link between these pesticides and bird health is becoming clearer.  A recent study done by Dr. Marc Bélisle of the University of Sherbrooke  found that barn swallows fare less well in areas of intensive agriculture where pesticides such as neonicotinoids are applied. Not only do the young have a harder time surviving, but adult birds suffer from lower body weight.

As for shorebirds like plovers and sandpipers, long-distance migrants have declined most steeply. Many of these nest in the Arctic and overwinter in Central and South America. Shorebirds depend on coastal areas and inland wetlands for breeding, migration, and wintering. Vital shorebird habitat is being lost to coastal development and suffers from human disturbance such as dogs running free on the beach. Key to their conservation is protecting migration stopover and wintering sites.

When it comes to forest-dwelling birds, the picture is more nuanced. Although more forest birds have increased (e.g., blue-headed vireo, pileated woodpecker) than decreased in the past 20 years, there are still many woodland species that are declining. The drop in warblers – often the most popular species with birders – is especially sad. As a group, they are down by 600 million. The cerulean warbler has been especially hard hit.

If you were to point to one reason for bird decline, it is loss of habitat. This is a problem not only on breeding grounds, but also during migration and where the birds spend the winter,  often in Latin America. This highlights the need for strong international conservation action.

The impact of climate change is also an increasing concern. The new superstorms, fueled by our warming oceans, can have a huge impact on birds and insects. Wildlife in Puerto Rico was devasted by hurricane Maria – even the bees. There is also a growing fear that long-distance migrants, which are declining faster than resident species, will not be able to adjust their migration schedules to coincide with the shifting peak abundance of their far away food sources. This effect is known as “decoupling” and is already a cause of seabird decline. Rising sea levels will also reduce available habitat for coastal nesting birds.

It’s not all bad news, however. Some bird groups are actually faring better. Since 1970, geese and duck populations have more than doubled, as have birds of prey like hawks and falcons. Big birds in general seem to be faring well, too, with 11 of Ontario’s 12 heaviest birds showing a marked increase in the past 20 years. Among these are the sandhill crane and the wild turkey.

Waterfowl in particular have benefited from investments in habitat conservation by government, non-government and industry organizations. Raptors have rebounded from their precarious population levels of 50 years ago thanks to the ban on the indiscriminate use of DDT.  When we understand the problem and act together, conservation works.

What to do?

As with climate change, individual action is important, but new laws and the investment of public money are key. Conservation charities can’t do it alone. Anyone voting with conservation in mind can’t help but be impressed with the Liberals commitment to protect 25 percent of Canada’s ocean waters and land by 2025 and to plant two billion trees by 2030. Both of these policies will greatly benefit birds and other wildlife. I fear, however, that a Conservative government would make deep cuts in the conservation and habitat protection budget in their rush to lower the deficit. Money for protected areas and endangered species is always seen as low hanging fruit for cost savings by fiscal conservatives.

Individuals can be part of the solution, too, by donating to conservation groups like Bird Studies Canada, buying bird-friendly shade-grown coffee, keeping cats indoors, planting shrubs and wildflowers in your yard, and making windows bird-safe (see Bird Friendly Homes at allaboutbirds.org). The most effective product to apply on windows is “Feather Friendly” dotted tape, which is sold at the Avant-Garden Shop in Peterborough.

The success in bringing back waterfowl and raptor populations is proof that conservation and legislation can work. I dream of the day when our fields and forests will once again reverberate with the variety and intensity of bird song that I knew as a teenager all those years ago on the William’s farm.

What to watch for this week 

We are fortunate that the peak colour of most red and sugar maples will coincide this year with Thanksgiving Weekend. Be sure to get out and enjoy the show. Two near-by areas with a great colour display are Gooderham, north of Buckhorn, and Chandos Lake, east of Apsley.

 

 

 

Sep 202019
 

Shifting dates, species declines, and surprising newcomers tell us climate change has arrived

For years we used to drive up to Algonquin Park in early summer to take our daughters to camp. One of the highlights of these trips was seeing moose along the side of Highway 60. Getting closeup looks and photographs of these huge and graceful animals was always such a thrill. Now, however, we rarely see them. Moose populations in Ontario have fallen by 20 percent – in some areas, 60 percent – in just the last decade. One of the main causes is climate change. These Canadian icons are poorly adapted to warmer temperatures. They are also dying from brainworm disease, which is arriving courtesy of the northward march of white-tailed deer. Deer are thriving as the climate warns.

Ontario moose are struggling with the warmer temperatures ushered in by climate change. Populations are down by 20 to 60 percent. (Randy Therrien)

White-tailed Deer (Stephenie Armstrong) 

 

 

 

 

 

 

 

 

 

Slowly but steadily, nature in Central Ontario and the Kawarthas is changing. New species are arriving, the dates of key events are shifting, and extreme weather events are becoming more common. For many years now, local naturalists and biologists have been noticing and documenting these changes. What the changes all have in common is a link to a warming climate.

A new timetable

Numerous events are now happening, on average, earlier in the spring, while others are occurring later in the fall.

·       In many parts of their range, bird species are arriving back earlier on their breeding grounds. These include common species like Canada geese, red-winged blackbirds, and tree swallows. The average egg-laying date for tree swallows is up to nine days earlier across North America.

·       According to an OMNR study from 2012, the peak calling period of early breeding frogs such as spring peepers is now 10-20 days earlier than in 1995.

·       Over the past decade or so, local wildflowers such as trilliums have often reached peak bloom in late April or early May, instead of the long-term average date of mid-May.

·       Earlier plant blooming also means pollen is being released into the air earlier. With more carbon dioxide (C02) in the air, plants are able to grow bigger and produce more pollen.  The pollen season is also lasting longer. Even in downtown Toronto, pollen levels are far above those recorded in the early 2000s. Data from the United States Environmental Protection Agency shows an especially big jump in the ragweed pollen season. In Winnipeg, for example, the plant’s growing season increased by 25 days between 1995 and 2015. If you are a hayfever sufferer like me, this is bad news.

Studies are showing a big increase in the length of the ragweed pollen season. It’s bad news for hayfever sufferers. (Drew Monkman)

Sugar maples (Cy Monkman)

 

 

 

 

 

 

 

 

 

·       On average, peak colour change in the fall leaves is happening later. Last year, for example, the best sugar maple colour was in mid-October instead of late September or early October.

·       The long-term average date for freeze-up of the Kawartha Lakes is mid-December, while the ice is usually out by about April 20. Since the early 2000s, however, the lakes have often been ice-free by early April, while freeze-up hasn’t happened until January. Later freeze-up means that waterfowl are lingering on local lakes until early winter. This trend can be seen in Peterborough Christmas Bird Count records, which date back to 1952.

 

Plant and animal populations

·       “Southern” birds are expanding their breeding range northwards into Central Ontario. These include red-bellied woodpeckers, which many people now see at their feeders.

·       A study based on 22 years of data from Project FeederWatch has shown that as minimum winter temperatures have increased, birds that used to spend the winter solely in the south are now wintering further north.

·       Virginia opossums and white-footed mice, both of which are southern species, have now extended their range into the Kawarthas. According to Trent University researcher, Dr. Jeff Bowman, bobcats – another southern species – are also expanding into Ontario. At the same time, the lynx’s range is contracting northwards.

According to Trent University researcher, Dr. Jeff Bowman, bobcats are expanding their range northward into Ontario and are expected to become more common. (Drew Monkman)

Flying squirrels at Sandy Lake near Buckhorn (Mike Barker)

 

 

 

 

 

 

 

 

 

·       Research done by Bowman and his colleagues has also showed that during a series of warm winters between 1995 and 2003, the southern flying squirrel rapidly expanded its northern range limit. Their study demonstrated that these southern species are mating with their northern counterpart, the northern flying squirrel. This has resulted in a hybrid zone right here in the Kawarthas. The researchers believe that the range expansion and interbreeding is a possible effect of climate change.

·       Southern butterfly species are also moving north into the Kawarthas. The most noticeable and common of these is the giant swallowtail, Canada’s biggest butterfly. Until recently, this species’ Canadian range was restricted to southwestern Ontario.

·       Although the past few summers have seen greatly increased monarch butterfly numbers in the Kawarthas, the long-term prospects for this iconic insect are poor. Climate change-related droughts and abnormal weather patterns along the Canada to Mexico migration route are impacting numbers, as are winter storms on the Mexican wintering grounds. Warming in Mexico is also expected to disrupt the monarch’s period of reproductive diapause (suspension). If diapause ends too early, reproductive success will suffer.

·       Insects such as mosquitoes and ticks are thriving in our warmer climate, with some new species spreading northward. In the past, their range was restricted by colder winter temperatures. The greater number of frost-free days is also allowing for a longer reproduction season. The black-legged tick, which carries the Lyme disease bacteria, is now well-established in the Kawarthas. Hundreds of ticks are submitted annually to Peterborough Public Health from all over our region. In the 1990s, this species was found in only one region of the province.

·       We are seeing a marked increase in the abundance of non-native, invasive plant species. These include common reed (Phragmites), dog-strangling vine, and garlic mustard. Non-native invasives are more adaptable to a warming world than most native plants. They also have mostly negative impacts on our wildlife.

Phragmites on a roadside south of Peterborough – Photo by Drew Monkman

Poison Ivy – always a longer stem on middle leaflet; leaflets often asymmetrical; shiny; usually droop down a little – Drew Monkman

 

 

 

 

 

 

 

 

 

·       Poison ivy is increasing both in abundance and in size. Its growth has been turbocharged by warmer temperatures and rising levels of carbon dioxide. The plants are also producing a more potent form of urushiol, the oily sap that causes the rash.

Concern for the future

By 2030, it’s expected that Peterborough will be about 2 C warmer in each season. We can also expect a huge increase in the number of days above 30 C. By 2060, temperatures are projected to be 5 C warmer. The climate of the Kawarthas will be like southern Pennsylvania today. What will this mean for our flora and fauna?

·       A number of iconic birds may no longer be able to breed here, their ecoregion (i.e., habitat requirements) having moved further north. The call of the common loon is likely to disappear from the Kawartha Lakes.

Common Loon (Karl Egressy)

Adult Round Goby (Michael Fox)

 

 

 

 

 

 

 

 

 

 

·       The health of our forests will suffer as a result of higher temperatures, drought, windstorms, invasive plants, insect pests, and fungal infections. Species such as white pine, sugar maple, and white spruce may disappear from the Kawarthas entirely as their climate zone will have moved north.

· As water temperatures increase, our lakes and wetlands will also be impacted. Although warm-water fish like large-mouthed bass should be able to cope, cool and cold-water fish like walleye and trout will struggle to survive here. The conditions may allow non-native fish like round goby to thrive and out-compete native species for food. There will likely be an increase in the types and abundance of other invasive species such as zebra mussels and Eurasian water-milfoil.

The changes we are seeing in nature in the Kawarthas represent a “canary in the coal mine” warning that climate change is happening now. But, like the proverbial frog in water that is slowly brought to a boil, we seem unable or unwilling to react to this sinister and deadly threat to the future of all life on the planet. The climate crisis should be top-of-mind when we cast our votes in October.

What to watch for this week

Southbound white-throated sparrows and dark-eyed juncos should be arriving in local backyards in the coming days. They are easy to attract by spreading millet or finch mix on the ground, preferably close to your feeder. The sparrows will linger for several weeks, before departing. Juncos sometimes stay all winter.

White-throated sparrow (Karl Egressy)

Juncos and white-throated sparrows feeding on ground (Drew Monkman)

 

 

 

 

 

 

 

 

Climate Crisis News

Be sure to drop by the climate-crisis booth at the Purple Onion Festival at Millennium Park on Sunday, Sept. 22. There will be information on how to reduce your personal carbon footprint as well as petitions to be signed to urge city council to declare a climate emergency as soon as possible. Other climate events scheduled for the coming weeks include the Global Climate Action Day (Sept. 27 at Millennium Park from 12:00-3:00 pm) and 100 Debates on the Environment (Oct. 3 at the Students Centre at Trent University from 7:00-9:00 pm.) The local candidates in the federal election will be taking part. This event had previously been scheduled to take place at Trinity United Church. 100 Debates for the Environment is a non-partisan, nationwide effort to highlight environmental issues in the election. More information can be found at 100debates.ca.

 

 

 

 

 

Apr 052017
 

Three recent studies point to just how broad, bizarre, and potentially devastating climate change is to life on Earth. And we’ve only seen one degree Celsius of warming so far.

Source: The Guardian   Author: Jeremy Hance    Date: Wednesday 5 April 2017

Climate change is rapidly becoming a crisis that defies hyperbole. For all the sound and fury of climate change denialists, self-deluding politicians and a very bewildered global public, the science behind climate change is rock solid while the impacts – observed on every ecosystem on the planet – are occurring faster in many parts of the world than even the most gloomy scientists predicted.
Given all this, it’s logical to assume life on Earth – the millions of species that cohabitate our little ball of rock in space – would be impacted. But it still feels unnerving to discover that this is no longer about just polar bears; it’s not only coral reefs and sea turtles or pikas and penguins; it about practically everything – including us.

Three recent studies have illustrated just how widespread climate change’s effect on life on our planet has already become.
There has been a massive under-reporting of these impacts. “It is reasonable to suggest that most species on Earth have been impacted by climate change in some way or another,” said Bret Scheffers with the University of Florida. “Some species are negatively impacted and some species positively impacted.” Scheffers is the lead author of a landmark Science study from last year that found that current warming (just one degree Celsius) has already left a discernible mark on 77 of 94 different ecological processes, including species’ genetics, seasonal responses, overall distribution, and even morphology – i.e. physical traits including body size and shape.

Woodland salamanders are shrinking in the Appalachian Mountains; the long-billed, Arctic-breeding red knot is producing smaller young with less impressive bills leading to survival difficulties. Marmot and martens in the Americas are getting bigger off of longer growing seasons produce more foodstuffs, while the alpine chipmunks of Yellowstone National Park have actually seen the shape of their skulls change due to climate pressure.

Click here to read entire article

Apr 052017
 

Source: The Conversation: Academic rigor, journalistic flair   Date: April 5, 2017  Authors: Gretta Pecl: Deputy Associate Dean Research, ARC Future Fellow & Editor in Chief (Reviews in Fish Biology & Fisheries), University of Tasmania; Adriana Verges, Senior Lecturer in marine ecology, UNSW  Ekaterina Popova: Senior Lecturer in marine ecology, UNSW; Jan McDonald: Senior Scientist, ocean modelling, National Oceanography Centre

Last year in Paris, for the very first time, English sparkling wine beat champagne in a blind tasting event. Well established French Champagne houses have started buying fields in Britain to grow grapes, and even the royal family is investing in this new venture.

At the same time, coffee-growing regions are shrinking and shifting. Farmers are being forced to move to higher altitudes, as the band in which to grow tasty coffee moves up the mountain.

The evidence that climate change is affecting some of our most prized beverages is simply too great to be ignored. So while British sparkling wine and the beginning of the “coffeepocalypse” were inconceivable just a few decades ago, they are now a reality. It’s unlikely that you’ll find many climate deniers among winemakers and coffee connoisseurs. But there are far greater impacts in store for human society than disruptions to our favourite drinks.

Dramatic examples of climate-mediated change to species distributions are not exceptions; they are fast becoming the rule. As our study published last week in the journal Science shows, climate change is driving a universal major redistribution of life on Earth.

These changes are already having serious consequences for economic development, livelihoods, food security, human health, and culture. They are even influencing the pace of climate change itself, producing feedbacks to the climate system.

Species on the move

Species have, of course, been on the move since the dawn of life on Earth. The geographical ranges of species are naturally dynamic and fluctuate over time. But the critical issue here is the magnitude and rate of climatic changes for the 21st century, which are comparable to the largest global changes in the past 65 million years. Species have often adapted to changes in their physical environment, but never before have they been expected to do it so fast, and to accommodate so many human needs along the way.

For most species – marine, freshwater, and terrestrial species alike – the first response to rapid changes in climate is a shift in location, to stay within their preferred environmental conditions. On average, species are moving towards the poles at 17km per decade on land and 78km per decade in the ocean. On land, species are also moving to cooler, higher elevations, while in the ocean some fish are venturing deeper in search of cooler water.

Why does it matter?

Different species respond at different rates and to different degrees, with the result that new ecological communities are starting to emerge. Species that had never before interacted are now intermingled, and species that previously depended on one another for food or shelter are forced apart.

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