Saturday, May 14, 2011

The Study Begins

After a year of proposal writing, planning, and presenting, the first field season of my Master's study in Raptor Biology is about to begin. Yesterday I finished the spring semester of my classes and tomorrow I will be heading for the hills, the South Hills that is. For the next 8 to 9 weeks my field assistant and I, along with other volunteers, will be performing a range of field studies all pertaining to my study species, the Northern Goshawk. The purpose of my study is briefly explained in my project abstract.


Forest structure has a profound impact on the species communities which live within its boundaries. The size and shape of a forest plot, the unique plant composition, and the proximity of the forest plot to other plots are among the factors influencing the species composition and dynamics over time. Anthropogenic impacts, both direct and indirect, can disrupt or accelerate the dynamic processes within a forest plot further shifting the species composition. Understanding how species utilize naturally fragmented habitat and how they respond to changes within that habitat can provide greater insight into their ecology and help prioritize management decisions to aid in conservation. The Minidoka Ranger District of the Sawtooth National Forest of Idaho, with its discreet forest segments and unique flora and fauna, presents unique challenges to sensitive species such as Northern Goshawks. The naturally fragmented forest structure found in the Minidoka Ranger District exhibits the constraints of island biogeography. The top identified food source of Northern Goshawks worldwide, tree squirrels of genera Sciurus and Tamiasciurus, are naturally absent from these forest islands. Additionally the Aspen forests upon which the Northern Goshawks locally depend are under threat from historic fire suppression practices and global climate change. I propose a multi-year thesis project to explore the breeding health of the local Northern Goshawk population by studying territory occupancy rates, breeding success, and fledgling sex-ratios relative to habitat quality, territorial prey abundance and predicted forest structural changes. The results will provide forest managers with information on the state of the Northern Goshawk population within the Minidoka Ranger District and the most significant factors affecting successful breeding within the population.

Much of our field time will be spent searching for Northern Goshawk nests. We will be visiting historic nests and checking for occupancy and systematically searching for new nests. We will be installing a total of six nest cameras to quantify what they are eating. Yes, tree climbing skills are critical. For each territory we will perform prey surveys every two weeks, counting every potential prey species observed. We will monitor the nest success and productivity, then lastly document the habitat structure of the nest stand.

All of this collected data will be processed over the next six months to answer the key research questions mentioned in the abstract. During this time, adjustments to the field processes will be developed for my second field season next year, when I will be doing it all over again.

As we head out to start this field season, a few challenges await. First and foremost is that the snowpack is two weeks behind average in melting. This follows many years of it melting earlier than average. The result is that there is still 36 inches of snow across much of the study area. We will be using snowshoes to start the season and some territories will just not be accessible. I am worried that previous studies have shown a very low nest occupancy rate in heavy snow years. The snow wasn't as heavy this year (only 20% above normal), but stayed much longer (snow pack now is over 200% of normal). I have a detailed day by day plan for the first week, which is now moot due to snow. I haven't even set foot in the study area and my plans are already out the window. This reminds me of one of my favorite quotes:

"In preparing for battle I have always found that plans are useless, but planning is". -Dwight D. Eisenhower

Lets hope my planning has enabled me to respond to these new challenges. And so I begin this journey with tremendous excitement and an open mind to let the season play out before me. What I do know for sure is that it will be a fantastic adventure. I will try to provide updates, although they will likely be brief.

Project is funded in part by a Challenge Cost Share agreement with the USDA Forest Service, the Mike Madder's Field Research Award, and Boise State University Raptor Research Center.

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