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Arichika Island declared rat free

By Quinn BenderHaida Gwaii ObserverWith Parks Canada and the CHN jointly declaring Arichika Island rat free, the work now begins to keep it that way. The news made national headlines last week when the two bodies announced the success of the eradication campaign on the small Gwaii Haanas island, beating tremendous odds to give a nesting seabird the fighting chance to bounce back from its Species at Risk status. "The introduction of rats to many of the forested islands of Haida Gwaii has meant the demise of several historic seabird nesting colonies," CHN President Peter Lantin said. "Of particular concern are the impacts that invasive rats have had on the ancient murrelet. This seabird was once an important food source for our people."Invasive species are considered the number-one threat to ecological and cultural heritage in Gwaii Haanas National Park Reserve. The ancient murrelet (SGin Xaana or "night bird" in the Haida language) was once abundant on Arichika Island, but in the late 1700s the Norway rat was introduced to the islands during the advent of maritime shipping. With an estimated 1.5-million nesting seabirds on Haida Gwaii, many of which are found on the remote islands of Gwaii Haanas, rat populations exploded in areas once revered as prime food-gathering places for the Haida. Consequently, the ancient murrelet, half of whose global population is found within the archipelago, is now listed under Canada's Species at Risk Act.But in 2009 the Night Birds Returning project was jointly launched by Parks Canada and the Haida Nation to restore nesting seabird habitat throughout the national park reserve. In 2011 a ground-based operation using rodenticide, daily monitoring and manual rat-carcass removal were largely successful on Arichika and Bischof islands. Two years later, on two larger islands rodenticide was dispersed by helicopter. Parks Canada says this is a proven conservation technique that's been used extensively in New Zealand, Mexico, the United States, countries from which organizations and experts contributed resources to the project in Gwaii Haanas.There have been more than 300 islands around the world where arial rat eradication programs have been successful. The campaign in Gwaii Haanas will be Canada's first. Monitoring of the efforts is showing positive results on all islands, but it's the complete eradication of Arichika island that has stakeholders celebrating. "Unless you get the very last rat, all of your efforts are for nothing," Ernie Gladstone, a Gwaii Haanas field unit superintendent for Parks Canada said. "We feel we're one of the few international leaders in this area of work right now. We're quite proud of what's happened here with this partnership and collaboration."Parks Canada worked closely with U.S.-based Bell Labs to design a bait that wouldn't react with the rats for up to 10 after consumption, eliminating the rat's ability to associate the poison with its source. Mr. Gladstone added the grain-based rodenticide was highly attractive to rats, but few other animals. But the work isn't done yet. Parks Canada is now appealing to the public to help them keep rat populations under control. They have teamed up with Parks BC and local harbour authorities on Haida Gwaii to provide every boat owner a so-called Rat Prevention Kit at no charge. "It's all in an effort to protect these islands that we've invested so much in, and to protect other seabird colonies around Haida Gwaii," Mr. Gladstone said. The kits consist of rodent traps, bait and information on how to both eradicate a problem on vessels and prevent it from occurring in the first place. The kits will be given to local harbour masters for distribution within the next couple of weeks.A Gwaii Haanas Speaker Series will also get underway April 29, at 7:30 p.m., at the Haida Heritage Centre to explain in detail how the program worked, and what needs to be done going forward. Back on Arichika Island, native bird species are already responding to the absence of rats. Populations of native shrews on both Arichika and Bischofs islands are already at levels comparable to islands without rats. Black oystercatchers, shorebirds which are considered by scientists to be sentinel species that respond quickly to changes in ecosystem health, are increasing in numbers and are fledging more chicks in the absence of rats. Automated acoustic listening devices have been deployed on these islands and on unaffected islands to measure seabird response to the eradication. Scientists will study the frequency and distribution of the birds' calls to gauge project success, as well as monitor a number of other ecosystem responsesParks Canada and the Haida Nation worked with several partners on the Night Birds Returning project, including Coastal Conservation, Simon Fraser University and Laskeek Bay Conservation Society, as well as United States-based partners Island Conservation, National Fish and Wildlife Foundation and the Luckenbach Council and Mexico's Conservacion de Islas.