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Since virtually all shrike habitat in Canada lies on private property, landowners play a vital role in saving this endangered bird.

In Ontario, Manitoba and Quebec, we’re working with supportive landowners, as well as researchers, funders and many volunteers, to bring the Eastern Loggerhead Shrike back from the brink of extinction.

Our efforts are based on a federal recovery strategy developed in 1996. They include:
Habitat Stewardship
Captive Breeding & Release
Wild Population Monitoring
Radio Telemetry & Geolocators
Genetic Studies & Stable Isotope Analysis

And while there’s still a long way to go to reach our goal of 100 breeding pairs in the wild in distributed among 3-4 populations in Ontario, the recovery program is making an impact.

Shrike habitat in Canada is shrinking: nearly all of the original grassland and savannahs have been plowed under or paved over, while much of the cattle pasture that provided a substitute has been abandoned in recent years. At the same time, increasing development is fragmenting much of the habitat that remains.

Habitat stewardship is therefore an important part of saving the Eastern Loggerhead Shrike.

Between 2001 and 2009, we’ve worked with landowners and volunteers to restore or improve more than 6800 hectares of key shrike habitat in Ontario alone. Over half of the wild breeding pairs in ontario are nesting on sites improved under the habitat stewardship program. Wildlife Preservation Canada coordinates the eastern loggerhead shrike habitat stewardship program thanks to funding from the federal Habitat Stewardship Program and most recently the Ontario Species at Risk Stewardship Fund.

Each site is different, but habitat stewardship projects could include:
• Installing or repairing fencing so that abandoned pastures can be grazed
• Removing cedars and other encroaching brush
• Thinning overgrown grasslands
• Planting shrike-friendly trees and shrubs for perching and nesting
• Enhancing water sources for livestock
• Fencing for keeping livestock out of wetlands and streams

In many cases, landowners have benefited from advice and grants to make their property attractive to Eastern Loggerhead Shrikes.

On Ontario’s Carden Plain/Alvar, a traditional shrike breeding area, we’ve also helped to spearhead the Integrated Carden Conservation Strategy.

This multi-stakeholder initiative has brought together naturalists, government representatives, farmers and ranchers, aggregate producers, and private landowners. Using a coordinated approach to habitat conservation and stewardship, it aims to save local species at risk, including the Eastern Loggerhead Shrike.

Although shrinking habitat is not the only cause of shrike declines, it is clear that habitat restoration work is making an impact. Today, more than half the wild Ontario population is nesting on properties that were enhanced or restored through the stewardship program.


In 1997, when the wild population hit a low of only 18 pairs, a captive breeding program was established for the Eastern Loggerhead Shrike.

A total of 43 wild nestlings were collected to set up a captive breeding population. The captive population was originally held at two locations: the Toronto Zoo and Montreal’s McGill University. The goal was to protect the genetic diversity of the population and, if possible, boost the numbers in the wild by releasing captive-bred birds.

The initial results were mixed – not a surprise, since little was known about how to raise shrikes in captivity. In 2001, however, when the captive population reached 100, we launched an experimental field-breeding and release program in Ontario that proved very successful. This program is spearheaded by Wildlife Preservation Canada.

This approach allows captive shrikes to raise their young in large wood and wire-mesh enclosures located in traditional shrike habitat. Parents teach the young shrikes how to fly, hunt and hide from predators — important skills if they are to survive in the wild.

At the end of each breeding season we release approximately 100 of these young birds in Ontario. Since less than five per cent of wild shrikes typically survive their first year, we need to release large numbers of captive-bred birds to make an impact.

In 2005 we made history when a captive-bred shrike was spotted on the Carden Plain, where it subsequently bred with a wild male and fledged five young. No other captive breeding program for a migratory bird has achieved this kind of success so quickly, just four years after the first releases.

Since then, we have seen more returns each year. In the 2008 season eight captive-bred birds were sighted in the wild, including two released in 2006 — the first time we have had release birds return to breed in consecutive years. In total, almost a quarter (22.2%) of wild pairs confirmed in Ontario in 2008 included a release bird. In 2009, an additional four returns, including a three year old captive/released bird.

Currently in Ontario we have field-breeding enclosures at two sites in southern Ontario, as well as over-wintering facilities in Ingersoll, Ontario, the Toronto Zoo, and African Lion Safari. The Avian Science and Conservation Centre at McGill University also breeds and releases captive birds.

To measure the success of the recovery effort, we need to track the number of Eastern Loggerhead Shrikes in the wild. To do that, we use colour banding — tiny bracelet-like rings that are loosely secured around the birds' legs.

Between 1999 and 2006, more than 1,000 adults and nestlings were banded using different colours to individually identify each bird, the year of banding and whether it was wild or captive-bred.

If the bird later shows up somewhere else — whether it's in another core area in Canada, or thousands of kilometres south in the United States — the bands will help researchers learn more about the shrike's behaviour and migration habits.

Monitoring the wild population is no easy task, since overlooking only a few pairs means missing a substantial percentage. If you're a birder and you spot a colour-banded shrike, be sure to report it by calling us toll-free at 1-800-956-6608.

Currently the number of shrikes in the wild is still very small — just 31 in Ontario in 2009. The number of wild pairs in Manitoba is in the single digits, and no breeding shrikes have been spotted in Quebec since 1995.

However, we have seen some encouraging trends. The population has nearly doubled since 1997, when only 18 pairs were left in the wild in Ontario. We’re also seeing shrikes reappear in several areas. In 2006, for the first time in many years, pairs were spotted in Ontario’s historic breeding areas of Renfrew and Smiths Falls and continue to be seen in these areas. In 2008 several birds on Carden Plain expanded into new territories and early results for 2009 show that this trend is continuing with two pairs confirmed breeding in Grey/Bruce where they’d last been confirmed breeding in 2002.



Where do Canadian shrikes spend the winter? What route do they take to get there? What percentage die before they can return to their breeding grounds?

We are slowly starting to piece together the answers to these questions, thanks to genetic studies and stable isotope analysis and reports of fall and winter sightings (two at Ontario’s Long Point during fall migration and one in Ohio in March 2007).

To get more detailed information, however, we launched radio-tracking programs in Ontario and Quebec. By fitting captive-bred shrikes with tiny radio-transmitters, we can track the birds by car or airplane.

The transmitters weigh only 1.4 grams and are attached to the back of the bird using a harness. Once it’s on, all that can be seen is a fine, thread-like antenna extending from the bird’s tail. Extensive testing has shown they have no physical or behavioural effects on the shrikes.

To date, we have learned that more than three-quarters of our captive-bred birds survive long enough in the wild to begin migration. So far, we’ve been able to track them more than 150 km as they head south, and we’ve learned that 75% of the cative bred/released shrikes survive to migrate.

Now we’re testing the use of geolocators. These instruments measure light levels and are now small enough to attach to the back of a shrike. Because day length on a particular date correlates to latitude, while the timing of sunrise or sunset correlates to longitude, this information will let us determine the timing of migration, the routes shrikes take and the location of their wintering grounds.

We’ll need to re-capture the birds to collect the data from the geolocators. However, with potentially 6.4 per cent of our captive-release shrikes returning, this is a real possibility.

Scientific research is helping us to learn more about shrike population dynamics: how the genetic make-up of groups of shrikes changes over time, and how different the genetics are from one group to the next.

To get that information, we remove a tail feather at the same time as we band each shrike. It’s a painless procedure for the bird, and the feather re-grows within six weeks.

Using the DNA in the feather, we can create a genetic profile of the bird. We can also track where it has been by analysing the feather’s stable isotopes — a chemical “signature” created by the different atomic weights of elements like carbon and hydrogen in different geographic areas.

Based on what we know so far, it looks as though individuals from other groups of Eastern Loggerhead Shrikes join the Ontario populations each year, bringing new genes into the local gene pool and helping to maintain shrike numbers here. In turn, some Ontario birds may join more southerly populations.

It also appears that Ontario shrikes spend the winter throughout the southern United States, especially along the Mississippi Velley and watershed system. Further research hopes to confirm specific wintering grounds and migration routes.



Saving an endangered species isn’t easy, but recent results of the Eastern Loggerhead Shrike Recovery Program show that we are having an impact.

The number of shrikes in the wild is consistently higher than in 2001, when we launched the captive breeding and release program as a last-ditch effort to save this highly endangered bird.

The captive-breeding and release program has proved highly successful: each year we release roughly a hundred captive-bred birds, which are proving they can survive in the wild, migrate successfully, and return to breed with the wild population. In 2008, 6.4 per cent returned to their Ontario breeding grounds — higher than the return rate of their wild counterparts.

Meanwhile, more than half of the wild population is nesting on restored or improved habitat, thanks to the efforts of many landowners, and we are slowly learning more about shrike migration patterns and population dynamics.

However, with only a few dozen pairs breeding in the Canadian wild, there’s still plenty of work to do before we can take the Eastern Loggerhead Shrike off the endangered list.

Manitoba Reports

Manitoba field report 2007
Manitoba field report 2006
Manitoba field report 2005

Manitoba update Winter 2004-05

Ontario Reports

Ontario field report 2009
Ontario field report 2008
Ontario field report 2007
Ontario field report 2006

Ontario field report 2005
Ontario field report 2004
Ontario field report 2003

Quebec Reports

Outaouais report 2006
Outaouais report 2005
Outaouais report 2004