Saturday, December 29, 2012

The Written Word

A thesis project is a large and daunting project. At times it can become overwhelming, although I do have a slight edge in this area with my past experience as a project and program manager of multi-year projects.

As many of you know, I am working on my master's thesis in Raptor Biology focused on the breeding ecology of the Northern Goshawk. I have completed the two field seasons successfully and am now focused on writing the thesis and submitting my chapters for publication. With a few additional side projects underway, you may have noticed that my blog posts have not been quite a regular as they used to be.

People take different approaches in the development of a thesis. Some will write a complete unified thesis and worry about submitting papers for publication at a later date. I was encouraged by my thesis committee to focus on the papers first, then simply include them as separate chapters of the thesis. The general idea is if you can get your chapters accepted for publication by a peer reviewed journal, the university shouldn't have anything else to say. I chose the later route.

Northern Goshawk, Sawtooth National Forest, 2012.

My thesis consists of three chapters. Originally I had only planned two chapters, but a recent GIS project that I worked on seemed appropriate for publication so my committee and I decided to include it.

Chapter 1: Indirect Effects of Prey Abundance on Breeding Season Diet of Northern Goshawks within a Unique Prey Landscape. This chapter summarized my quantification of the diet of the goshawk using nest cameras. I have submitted it for publication to the Journal of Raptor Research. They have had it in their hands for nine weeks now, so I hope to hear back any day. With the holidays it will probably end up being mid-January.
Chapter 2: Predicting Nestling Habitat of Northern Goshawks in Mixed Aspen-Lodgepole Pine Forests in a High-Elevation Shrub-Steppe Dominated Landscape. This paper is largely based on Geographical Information System (GIS) analysis, using model selection to prioritize areas for nest searching. In additional to a master degree, I am also completing a Graduate Certificate in Geographical Information Analysis and this chapter meets my final deliverable for that program. While I did not use this full method in the field, I was able to find five additional nesting territories using GIS analysis. I have submitted this chapter to the Open Journal of Ecology. They have only had it for one week, so I don't expect to hear back from them soon.
Chapter 3: Effects of Prey Abundance and Forest Structure on Occupancy and Productivity of Northern Goshawks Within a Unique Forest Landscape of the Western United States. This chapter addresses the core question of my thesis. Unfortunately, my results didn't come out strong. I and my committee still believe it is worth publishing, but we have not yet decided on where to submit it. I am targeting submission of this chapter to a journal by the end of January.

The first side project I have in the works is a study of blood parasites among the nesting goshawks I studied for my thesis. This project is being led by a friend of mine, Michelle, but I am helping her count parasites, analyze the data, and complete the manuscript for publication. We hope to submit the manuscript to the Journal of Raptor Research some time in the spring. The project began when I was told that the goshawks in the south hills had a low survival rate, most likely the result of a blood parasite. I recruited Michelle to lead the project. We have since collected a fair amount of data that indicates that the infection rate is very high, but the survival rate appears to be strong. It is an exciting project and will be a great accomplishment for Michelle, myself, and our other co-authors.

The biggest project challenge going forward is an analysis and manuscript I am leading focused on the the effects of climate change on the migratory timing of songbirds and raptors through southern Idaho. One of my co-authors presented this work at the North American Ornithological Conference in August as part of a special symposium on climate change. As a result of that conference, we were invited to submit a chapter for a special edition of Studies in Avian Biology. Manuscripts are due in June and the edition is supposed to go to press at the end of 2013. We are revising the analysis and updating our manuscript.

There is a lot more to research than the field work and documentation. I am now in the "speaking tour" phase of the project. Last year I presented preliminary results at the Raptor Research Conference and in October I traveled to Portland to present at the national Wildlife Society conference. Upcoming events include presentations at the Great Basin Consortium in Boise in January, my thesis defense February 22, and the Idaho Chapter of the Wildlife Society conference in March ( Coeur d'Alene). I will also present the climate work at that conference. There are public outreach presentations as well. I have already presented at the Peregrine Fund and the Prairie Falcon Audubon Society (Twin Falls). In February I present at the Southwestern Idaho Birders Association in Nampa (Feb 14) and the Golden Eagle Audubon in Boise (Feb 26). All of these outreach events are open to the public. Let me know if you need information.

If my fingers survive the typing and my voice survives the presentations, I guess I will try to figure out what to do when I grow up. I quit my previous job in January of 2009, to pursue this goal of working on field research. By all accounts it has been tremendously successful. I would like to continue spending time in the field and delivering science that helps advance our knowledge and conserve the species that occupy our world. I'll keep you posted...

Wednesday, November 28, 2012

Fall Raptor Migration

The end of October brought the end of one of my fall projects - trapping and banding migrating raptors at the Idaho Bird Observatory. This year, with a lighter class load, I was able to spend more time on the mountain. I was up there at least 2 days a week and sometimes as many as five. It was a great time with a lot of great birds.

American Kestrel - Male.

In total, I trapped 16 days and banded over 220 birds. Between the two trapping stations (Lucky Peak and Boise Peak), our team banded over 1100. It was a pretty good year!

The highlight of the season for me had to be my solo trap of two juvenile goshawks at the same time.

Two juvenile Northern Goshawks - male left, female right.

It was all quite unexpected. I was trying to catch a Merlin, another favorite bird. They are fast and fleeting. The Merlin dove close to the "mist net" but pulled up at the last moment and flew on by. I twisted to see if it was circling back around when I saw a large bird hit the net! I didn't even see her. I ran out and extracted the first goshawk from the net. I often invite others to join me in the blind, but on this day I was working by myself. I returned to the blind to process the goshawk. As I sat down, another bird caught my eye. The other goshawk was going after my dove! I hadn't even pulled the lure. Holding the first goshawk in one hand, I leaned over and trapped the second with my only free hand. Yikes, what do I do now!?! I quickly put the first in a "can" as I ran out and retrieved the second. Awesome day and a great comparison of the size difference between male and female goshawks! The goshawk is always my favorite as I have spent the last 2.5 years studying them for my master's thesis in raptor biology. I caught a total of four this year.

While I am partial to goshawks, there are more rare birds to catch. While Swainson's hawks are common in our area, we have only ever captured three of them in 17 years of trapping. That is until I trapped the 4th this year.

Juvenile Swainson's Hawk.

This might have been a more exciting bird had I realized what we had trapped at the time. Without taking a close look at the bird, I originally identified it as a juvenile Red-tailed Hawk. I passed it off to be banded by an assistant, and I went on trapping. It wasn't until I saw the photos that it clicked. That was no Red-tailed Hawk! That was an important lesson that I will not make again!

Juvenile Red-tailed Hawk (one of eight I caught this year).

Merlins are always a favorite. I would catch a total of five this season. Like goshawks, they often commit to their prey from a distance out and come in hard and fast. We also have three possible sub-species that migrate through Idaho and it is always exciting to see what you caught. However, I have only even caught the primary sub-species - Taiga or Tundra Merlin - Falco columbarius columbarius.

Taiga Merlin.

During my first day of trapping this season, late in the day, I was visited by a unique American Kestrel. This male bird had all of the markings of a normal Kestrel, but lacked much color on the breast. A few times during the season, presumably this same bird, came by late in the day. Finally, on my last day of trapping, I got him.

Male American Kestrel.

The bird had normal streaking on the chest, but lacked much background color. Just two feathers had the expected buff color.

American Kestrel.

Sometimes we catch non-raptors. Last year Neil caught a Northern Shrike. This year, I was surprised by a Steller's Jay in my net!

Steller's Jay.
Steller's Jay.

It was a great year. I look forward to another one next season!

Saturday, November 10, 2012

River Otters Frolicking!

Here it is November and I haven't finished my blog posts from August! I guess that is what the final year of graduate schools does to a person. I've been busy working on three chapters of my master's thesis as well as two other side projects. But here it is....

In August, Karyn and I traveled to Alaska (click here for all of my posts on this trip). On our final day of the trip we were in Seward and had to get in one more hike. As it had been doing for a few days, it was raining - fairly hard. On our list of things to do, we wanted to see salmon spawning. We decided to undertake the short hike toward Tonsina beach before our drive back to Anchorage. The full hike to Tonsina beach requires coordination with a tide schedule as a portion of the trail is underwater at high tide. We were only hiking the 1.5 miles stretch to the first stream crossing. It would turn out to be a spectacular trip.

River Otter!

Half way to the bridge we noticed movement beside the trail. River Otter. One...Two...Three...Four! One of our favorite mammals. They were very curious and had to come and check us out.

River Otter.

Their attention span was short. After a quick check on us, they went back to focusing on each other. Any time we would move, they would come back over to check us out. Most of the time they just frolicked around with each other, never holding still.

River Otters.
River Otters.

We couldn't manage to pull ourselves away. Here is a quick video that Karyn took.

After twenty minutes of watching we had to move on. We had arranged for a late checkout from our hotel and we were on a schedule...

We continued down the trail arriving at the spawning stream. There were quite a few fish around.

Spawners!

Of course, where there are fish, there are eagles... and lots of them...

Seven Bald Eagles!
Four more!
Bald Eagles.

There were more eagles on the beach. We counted more than 20 in total. I am sure there were many more around. It was a spectacular sight.

We hoped to get one more glimpse of the otters on the way back through, but it was not to be. Unfortunately that bought an end to our fantastic trip to Alaska. We definitely plan to return some day.

Sunday, September 23, 2012

Its Time to Molt!

In the bird world autumn brings another major life event for many species - migration. For many this will be their first trip south following some route that has been permanently imprinted in their genes. Most are not guided by parents or even other members of their species. It is often a lonely journey of a single bird flying alone.

As a raptor biologist I study migration. My masters thesis is actually focused on breeding season ecology and not migration, but my undergraduate research focused on migration and I continue to work in the area out of personal interest. I have published one paper on the subject (Miller et al. 2011) and have a second paper in the works (recently presented at the North American Ornithological Conference in Vancouver).

My migration work is performed in conjunction with the Idaho Bird Observatory. I have used their 17+ years of migration data in the analyses I perform. I have also helped collect that data for the past four years banding songbirds, counting migrating raptors, and banding raptors. This fall most of my effort has been in the last category trapping and banding migrating raptors. I have spent two to three days a week siting in a blind trapping and processing these impressive migrants.

The data collection serves many purposes. Banding birds helps us to understand migration routes, breeding and wintering locations, and resource use which is important for conservation purposes. Most of my analyses have been focused on the timing of migration in response to weather and climatic events. Increasingly I have been looking into the body condition of these migrants in response to climatic events which can help paint a picture of changing prey availability. It is a complex picture, but the large dataset amassed by countless volunteers over the past two decades provide convincing evidence of change.

On a lighter note, one of the most impressive aspects of this data collection are the opportunities to examine individual birds up close and personal. We have been trapping raptors daily over the past month. So far we have banded over 600 raptors (143 for me personally!). The season generally starts out with us capturing primarily juvenile birds. This isn't just because they are easier to trap (they are), but in many species the juveniles migrate before the adults. There are differing hypotheses as to why this is such as adults can stay on breeding grounds longer as prey declines as they are better hunters or adults need to stay on breeding ground to molt feathers. In some species the males and females migrate at different times. This is supported by differing molt strategies between the sexes, differing migration distances between the sexes and differing prey requirements as the larger females require more food. If you are getting a sense of how complicated the study of migration can be, you are absolutely right.

Now that we are hitting the peak migration season, we are starting to see and trap more adult birds. This allows closer analysis of the subtle distinctions in ages of birds. We analyze age primarily through molt patterns in the feathers. Juvenile bird have all juvenile plumage. These birds are referred to as "Hatch Year" birds. Adult birds that have retained some juvenile plumage can be safely said to be "Second Year" birds (1 year old). If an adult bird has retained (old) adult feathers then it is at least "After Second Year". If it is an adult and we cannot find any old feathers, we cannot tell if it is a Second Year, Third Year,... only that it is "After Hatch Year."

However, in some of the larger birds that might not molt all of their feathers in a single year, we may be able to do better. We have recently started collecting more data which may help us more precisely age these individuals. We are now looking into the molt patterns of the primary, secondary, and tail feathers in the hope to identify patterns unique to different ages.

Figure 1: Adult Cooper's Hawk.

I have included a couple of photos which may help illustrate this point. The Cooper's Hawk generally molt all of their feathers every year, but there are unique patterns in how they do it. The Primary feathers are the 10 feathers (most species) at the tip of the wing that extend out from the hand of the bird. These are called flight feathers as they are strong feathers that help support the bird in flight. Secondary feathers extend back from the forearm and are also flight feathers. Whereas contour feathers are body feathers which may help smooth the air, but also provide insulation. The primary feathers are numbered starting at the break between the primaries and secondaries and extending out toward the tip of the wing. Most birds begin the annual molt by replacing P1, then P2, ... In Fig.1 you can see that this adult Cooper's Hawk has replaced P1-P5, P6 is nearly complete, P7 is only 30% complete, and P8-P10 are retained feathers not yet shed. In Fig. 2 (different bird) the pattern is nearly the same except P7 is at 70% and P8 is not visible as it is only about 10% grown.

Figure 2: Adult Cooper's Hawk.

The secondary feathers are counted starting at the break with the primaries and moving in toward the body. This numbering system is consistent with the general way that birds molt the secondaries. In large birds such as eagles, a second wave of molt may being at S1 before all of the previous secondaries have been replaced resulting in 3 or 4 different age feathers along the wing. In these situations more precise aging is possible.

Accipiter Hawks (in North America: Sharp-shinned Hawk, Cooper's Hawk, and Northern Goshawk) exhibit a modified version of this molt strategy. They molt the primaries starting with P1 and moving toward P10. This is illustrated in both Cooper's Hawk photos. The Northern Goshawk will sometimes not complete this within a single year and a second wave will start behind the first during the next year. For the secondaries, Accipiters begin with S1 moving toward S4, but will also start with S5 moving toward S10. In Fig. 1 you can observe both S1 and S5 being replaced. In Fig. 2 S1 and S5 are fully in and S2 is still growing. On most birds both wings will be symmetric in the molt. However, if a bird loses a single feather not associated with molt, that feather can be replaced at any time of year. This is called adventitious molt and complicates the interpretation of molt limits.

Molt limits are not restricted to the wings. The tail is also composed of flight feathers which are replaced in specific patterns. The tail feathers are counted from the center toward the outside. The Cooper's Hawk in Fig. 3 has replaced T1, T3 and T4. T2 and T5 should be next followed by T6.

Adult Cooper's Hawk tail.

The thing I like about trapping and banding raptors is the opportunity to experience these magnificent creatures on many scales. We observe the migratory timing on the population scale, the molt strategies on a family scale, the hunting strategies on a species scale, and the body condition on an individual scale among many other things. Every day I spend on the mountain I come away more in awe about these predators and grateful that I have focused my career on their preservation.

We catch a lot of Sharp-shinned Hawks and Cooper's Hawks, but also many other species. So far I've trapped seven Red-tailed Hawks this year including my first dark morph (color morphs are a whole other issue). Here's two different juvenile Red-tailed Hawks.

Juvenile Red-tailed Hawk.
Juvenile Red-tailed Hawk.

Another favorite are the Merlins. There are three subspecies that we can catch, but all of mine have been the columbarius sub-species.

Merlin - Falco columbarius columbarius

Sources:

Pyle, P. 2005. Remigial Molt Patterns in North American Falconiformes as Related to Age, Sex, Breeding Status, and Life-History Strategies. The Condor 107:823-834
Pyle, P. 2008. Birding by Feather: A Molt Primer. Birding. 18w1-18w6.

Paddling in the Rain

Welcome to the fifth installment summarizing Karyn and my recent trip to Alaska (all of the stories are here). After visiting Barrow and Denali, we settled into Seward for the final days of our adventure. The rain joined us there after beautiful sunshine for most of our trip. We didn't let that discourage us!

We were hoping to experience some sea kayaking. Unfortunately we hadn't made reservations far enough in advance to join the tour to see glaciers calving into the bay. We settled instead for a wildlife tour at Fox Island. We awoke to a downpour. Not to fear, we own a fair amount of Goretex!

Paddling in the rain. Resurrection Bay Alaska

The trip began with a ride on a large boat out to Fox Island. The boat stopped just long enough for us to jump off and then continued on its way. We were the only two customers for this kayak. We met up with our guide Betsy from Sunny Cove Sea Kayaking company and gabbed our gear. The local caretaker informed Betsy that two River Otters had slept in her kayak the previous night! We checked for any unwanted waste left inside, but it was all good. It continued to rain!

Our destination was to paddle out around the point and into Sunny Cove. That sounded great! Betsy promised that it would be sunny there. No worries.

Guide Betsy.

Sea birds flew around us, fish jumped, and the rain fell. It was beautiful.

Point of Fox Island.

We circled around the point and into Sunny Cove. Horned Puffins, Common Murres, Pelagic Cormorants, Black-legged Kittiwakes. It was great. We checked out sea stars on the rocks and Bald Eagles overhead.

Bald Eagle in the mist.

Harlequin Ducks, Black Oyster Catchers, Marbled Murrelets, Pigeon Guillemots! This was a pretty diverse list of birds for a few hours in a kayak. Wait, where's the sun? Sunny Cove is a LIE! It was still raining! It doesn't matter, we were enjoying ourselves. The puffins were the best. They circled around us and landed on the rocks nearby.

Horned Puffins!

We even got to see Jellyfish. I had never seen striped ones before.

Striped Jellyfish.

The highlight of the day was the River Otters. We had expected to maybe see Sea Otters, but two River Otters came to check us out. Maybe the same two that slept in Betsy's kayak.

The first just swam up and looked at us, circled and then moved on its way. The second one, however, had just captured an Eel. He proceeded to eat it nearby. It almost looked as if he wanted to stay near the kayaks during lunch. Maybe he knew that he was safe with us.

River Otter with an Eel!

More Bald Eagles and more seabirds and our paddle was over. We had lunch at the lodge before a different boat came to pick us up. We circled fox island before heading back to Seward.

As this was a wildlife tour, the captain worked us in close to some seabird colonies. Horned Puffins and Common Murres dominated, but we also saw Tufted Puffins, Guillemeots, murrelets, etc. Had it not been raining, I probably could have had a few more life birds, but it was pretty spectacular the way it was.

Seabird colony!
Horned Puffins, Common Murres, and Black-legged Kittiwakes!

Another great day on our Alaska adventure. Only one day remaining, but it too was full of surprises. I will highlight it in the next post.

Monday, September 03, 2012

International Vulture Awareness Day 2012

This last Saturday was International Vulture Awareness day. I hope you had the opportunity to share some vulture love and help educate the world about the plight of these critical creatures. As Karyn and I have done in the past, we volunteered at the Peregrine Fund's World Center for Birds of Prey to help educate children. Our task was to engage the kids in the creation of a vulture paining. As you might guess, this falls heavily on Karyn the artist, but I participate as her dutiful assistant and provide moral support.

Final Painting.

Our painting activity wasn't the only activity that day. There were other children activities and bird presentations throughout the day. Two of the bird presentations featured "Lucy" the Turkey Vulture.

Lucy - Turkey Vulture.
Lucy - Turkey Vulture.

Karyn prepared the canvas before the event with a sketch of what we had hoped to achieve. This sketch was reproduced from a photograph that I had taken a few years back at Centennial Marsh.

Initial Sketch.
Enthusiastic First Artist.

Each child that comes through gets to apply some paint to the canvas. We usually let them choose what they want to paint, but then guide them to where they may be most successful based on age and skill level.

One challenge faced during the day is trying to determine how much to encourage them to paint. We wanted one painting to last all day, but also wanted it to be completed by the end of the day. As the attendance was generally lower than last year, we let most kids paint as long as they wanted.

Starting to take shape.

As you can see Karyn takes most of the burden when it comes to directing the kids. I take photos, refill water, and direct a little when we have more than a few kids at a time.

We even had an angry bird show up to paint.

Angry Bird Painting
Almost done.
Final Painting.

In the end we had about 20 kids participate on the painting. While there were fewer kids than last year, each got to participate for a longer amount of time. We hope that this helped the kids take a way a stronger message with regards to the importance and beauty of vultures in our world. Take another look at Lucy. What's not to love?

In addition to this activity, I also made a short presentation on the world vulture crisis to two of the Biology Labs I teach at Boise State University.

Wednesday, August 29, 2012

We See the Sea Life at the SeaLife Center

Here is the fourth installment summarizing Karyn and my recent trip to Alaska. This was also based in our final destination of Seward.

After beautiful weather for most of our trip, the storms finally caught up to us. Actually it rained during our trip from Denali to Seward and also during our Harding Ice Field hike. But the forecast increased the probability of precipitation to 90%. They should have just said 100%. No worries, we were planning to visit the Alaska SeaLife Center anyway.

Tufted Puffin.

The SeaLife center is a large aquarium and animal rescue/rehabilitation center. It is also the base of operations for a fair amount of conservation science partnering with the University of Alaska Fairbanks and various agencies. We would spend most of the day there enjoying everything they had to offer. We even left for lunch and came back in the afternoon!

Horned Puffin.

The facility houses an extensive education center focused on marine life in general, native Alaskan cultures, and the life-cycle of salmon. But I was drawn to the large facility housing many types of sea birds. I have been to a number of aquariums before, but never one that integrated sea birds into the exhibit. You could watch them from inside through the glass, outside near the tank, or downstairs underwater.

Juvenile Tufted Puffin.

After taking a hundred or so pictures of the various birds, I went inside to sit and watch. Here I perused the bird guide to make sure that I could identify each of these birds in the wild, focusing on each of the distinctive features. We had a boat trip planned for the next day so I wanted to be prepared.

Rhinoceros Auklet.
Pigeon Guillemot.
Red-legged Kittiwake.

While I was intently studying the birds, Karyn was trying out the video features on our point and shot camera. Watching puffins swim underwater is amazing. They are definitely better swimmers than fliers in my opinion. This first video highlights a Horned Puffin swimming.

Almost as good was watching the Tufted Puffins bathing. They roll fully upside-down in the water. It is hilarious! Take a look.

Being a rehabilitation center, the "I Sea U" are regularly called upon to take care of stranded mammal pups. Harbor Seals, Sea Otters, etc. They recently rescued three stranded Pacific Walrus calves. Two didn't make it, but one is still alive and kicking. They require a great deal of contact so an employee or volunteer are always in the cage with the animal, 24 hours a day. The walrus would play in the pool and then interact with one of the volunteers. We were lucky enough to be there during feeding time. That was easy to do since we spent all day there! The staff mixed up and heated about a quart and a half of formula and delivered the goods. It was gone in less than a minute! Wow, that was cool. This guy weighs over 300 pounds and is growing quickly.

Walrus.

The Harbor Seal on display was another rescued animal. He was cool to watch as he swam deep under the water, surfaced, then swam belly up across the surface of the tank.

Harbor Seal.
Harbor Seal.

There are at least two more reports to follow. Next up is a summary of our Sea Kayak adventure observing all kinds of wildlife. Check back soon.