Thursday, March 29, 2012

Neither snow nor rain nor sleet nor wind...

Phase three of spring break consisted of a visit to Leslie Gulch for camping, hiking, and bird watching. Phase one was mountain biking and hiking and phase two was a visit to Malheur National Wildlife Refuge.
Leslie Gulch is only about a 90 minute drive from Boise, yet for some reason I had never been there before. I was always under the impression that it was a small canyon with only a single hike. While the area isn't really that large, it was much more diverse than I expected, provided pretty decent bird watching, the rock formations were spectacular, and had a number of hiking options. However, similar to Malheur it was still very windy!
American Kestrel.
Other than the wind, the weather wasn't bad on our arrival. We set up camp at the Slocum Creek campground near the reservoir. We decided for an evening off-trail hike up a nearby canyon. The rock formations were much more elaborate than I had expected. It was somewhat like a mini canyonlands. Western Meadowlarks sang as raptors and ravens kited in the wind over head. Chukars braved the threat of the raptors to find a high perch to enable their call to echo through the canyons.
Chukar.
The morning weather was not quite what we had hoped, but it was indeed spring break. For every spring break I can remember, it has snowed on me at least once! This was no exception.
Wind, rain, sleet, snow...
The first hike of the day was up Dago Canyon. This canyon has dirt road up the canyon, but it is gated so there were no vehicles. We hiked up a ways and then turned off up a side canyon to get into some slot canyons. This might not have been the best idea given the rainy conditions, but as long as it was a light rain and not a thunderstrom, we figured that we would be all right. We explored a few branches in the canyon until the trail got too narrow to proceed.
Dead end.
The canyons were filled with Western Meadowlarks, Chukar, American Robins, Northern Flicker, and Spotted Towhees. We were surprised to find a pair of Mountain Bluebirds braving the weather. The highlight, and one of my favorite birds, was a Canyon Wren singing in a rock backed ampitheater! Actually we would hear and see a number of them throughout the day. Their song is amazing! My first of the year Say's Phoebes joined us at lunch.
Say's Phoebe.
Rock formations.
After lunch the weather started to improve! The second hike of the day was up Juniper Canyon. As we were preparing at the trailhead I glanced up to see a falcon. Not just any falcon but a Peregrine Falcon. I know I say this a lot, but the Peregrine Falcon is "one of my favorite birds"! The Peregrine Falcon holds an extra special place in my heart as I know the history of this species. This species was threatened with extinction through human caused means. The human race realized this and adapted. The Peregrine Falcon was an instrumental species in getting the single greatest piece of legislation passed through the US congress, the Endangered Species Act. The Peregrine Falcon was one of the first species to be listed (if not the first), and was one of the first to be removed due to successful recovery (it might have also been the first to be removed). This offers hope that we as humans can adapt and help the natural world survive. To see a wild animal that had we not changed our ways would no longer be with us, is awe inspiring.

As I watched, the Peregrine rolled into a stoop! It rocketed downward. There in front were two Common Ravens soaring in the wind. The ravens barely evaded a direct strike. The Peregrine looped back up and came down again, this time making contact with one of the ravens! The ravens moved out as the Peregrine returned to circle overhead. I hate to anthropomorphize, but you cannot tell me that the falcon wasn't having fun messing with the ravens!

Blue sky! The blue sky emerged as we made our way up Juniper Canyon. Cool rock formations, singing birds, and three Golden Eagles kiting above the ridgeline. It was a great hike.
Rockin the sunshine!
Karyn near the top of the canyon.
Top of the canyon looking down.
We finished the hike just as the rain began to fall once again. We will definitely be coming back here!

Wednesday, March 28, 2012

Blowing in the Wind, Soaking in the Tub

This spring break consisted of a collection of various activities. The first weekend presented Boise with unseasonably warm weather so we stuck around and combined a morning bird hike with an afternoon mountain bike for each of the first three days. Then the weather turned as we headed to Malheur National Wildlife Refuge in Eastern Oregon for some spring bird watching. We were hoping to get there to see tens of thousands of snow geese before they headed north to the arctic. We would indeed see thousands of geese, they were scattered everywhere you looked!

Small group of Snow Geese.

As it has been every other time we have been there, the weather was nasty. Scattered rain and a 15-25 mph wind. Regardless, we would see 60 different species, even before the migrants showed up! Most were water birds.

Sandhill Cranes, Snow Geese, and Northern Pintails among others.

Of the various water birds, grebes have always been my favorite. Their general attitude, their diving ability, and their synchronized mating dance, which we saw, but just missed capturing on film.

Clark's Grebe.
Clarke's Grebes just finishing their mating dance.

For those of you who know grebes, you know that Carke's and Western Grebes look very similar. Well, that is until you see them side by side! The color of the bill and fact that the black surrounds the eyes of the Western are the most notably differences. I hadn't realized the size difference until we took this photo.

Clarke's Grebe (far) next to Western Grebe (near).

We had hoped for other grebe species, but those would remain elusive.

Our favorite part of the refuge, the central road, was not good this time around as the ponds bordering the road were not yet flooded. Most all of the birds we saw were out on the boundaries of the rufuge right off the highway. The refuge visitor center grounds were also good with a pair of Ruby-crowned Kinglets, Spotted Towhee, etc. The most impressive part of our visit was the unbelievable number of Northern Harriers. Anywhere on the refuge you could look around and somewhere see a harrier flying over the marsh. On many occasions you could see three of four at a time.

Male Northern Harrier.
Female Northern Harrier

Overnight we stayed at the Crystal Crane Hot Springs. Nice place to park our van, a very nice private tub, and very affordable. I recommend it if you visit the area.

Sandhill Crane.
Great Egret.
Yellow-headed Blackbird.

From Malheur, we headed further into southeastern Oregon to visit Leslie Gulch on the Owyhee Reservoir for some more birding and hiking. That will be deferred to the next blog post.

Thursday, March 22, 2012

Downy

Downy Woodpecker, Northend Boise.

Tuesday, March 20, 2012

Monday, March 19, 2012

Bohemian Waxwing

Bohemian Waxwing in Hull's Grove Boise, Idaho

Sunday, March 18, 2012

Forest Management Actions

We perform science for a number of reasons. In the medical field the focus may be on understanding the methods used by pathogens and how to combat those agents or evaluating the health impacts of contaminants. In the ecological field we often focus on the mechanisms operating within an ecosystem to better understand the natural processes and the impact of humans on those processes. This knowledge can help us to predict trends within a population, but also to recommend management actions which address the underlying influences on those trends instead of simply focusing on the trend itself.

My thesis research on Northern Goshawk Breeding Ecology includes a few of these objectives. The primary purpose of the study is to establish management recommendations which can help ensure that the ecosystem health is maintained. This health is balanced upon and measured by the presence of a strong apex predator population, one of which is the Northern Goshawk. To establish these recommendations we must first advance our knowledge of the species and how it uses this unique forest habitat. This knowledge advancement is the core of my thesis research.

The context of my study area forest is very important to this prioritization. In most forests the Northern Goshawk's role may not be as critical as in the South Hills of the Sawtooth National Forest. In the South Hills the forest is very heavily naturally fragmented and geographically isolated from other forests. The result, through the ecological function of island biogeography, is lower species diversity. Species diversity on islands is related to the size of the island and the distance to the next island or mainland. The South Hills forest is essentially an island of forest habitat removed from other islands by a sea of sagebrush, grassland, agricultural fields, and human development. With lower species diversity, the role of each species in the ecosystem can be amplified and the stability of the ecosystem much more easily disrupted by external forces either natural or anthropogenic (human caused). A side effect of this "island" influence, and one reason why my thesis is novel, is the natural absence of tree squirrels within this forest. It is estimated that tree squirrels disappeared from the area at least 10,000 years ago through unknown causes. Tree squirrels have been shown to be the top dietary choice of Northern Goshawks around the world and their abundance being the most influential factor in Northern Goshawk nest success.

My preliminary results show that during the core breeding season goshawks are consuming at least 2/3 of their diet in Belding's Ground Squirrels. This may not seem like such an significant shift, until you realize that unlike tree squirrels, Belding's Ground Squirrels are only available for 3-4 months of the year. They are still hibernating when nest site selection is made by breeding goshawks and they estivate (summer hibernation) before the goshawk fledglings have become independent. This explains why my second finding indicates that avian prey abundance and not squirrel abundance is the most influential on goshawk nest occupancy in the South Hills. In fact, mammalian abundance was dropped from all of my top predictive models. This is not to say that they are not critical for success, I believe they are, but simply that their abundance is not a good predictor of nest occupancy.

But lets get back to the management recommendations. Within my annual report I was asked to provide a list of management recommendations. While there are no expectations that they all will be fully implemented, I still took this responsibility very seriously. It would be easy to say that all human influences and disturbance should be removed. This would not only be ignored, it does not represent what my study findings show. I believe in wild untouched places and truly wish that we had more of them available. However, humans have touched and influenced nearly every place on earth. If we are not willing to sit back for 10,000 years just to see what happens, our previous influence warrants continued management in many areas. The South Hills are no exception. When I began this exercise I was expecting a much stronger view against disturbance and active management, but surprisingly that is not what I recommended.

Disturbance: Disturbance has been widely shown in many studies of many birds to have a detrimental effect on nest productivity. However, many of the South Hills goshawks have been well habituated to noise. One nest is just 50m from the busiest campsite in the area and is successful most years. Another has an ATV dead-end turn around at the base of the tree. Many nests are within 200m of a road or ATV trail. This speaks more to the number of roads and trails than to the goshawks preference for these roads. Some of the most successful nests were in high disturbance areas. However, the two goshawk nests that we discovered that failed were both subject to high disturbance (anthropogenic and natural). The first was within 100m of the busiest road in the South Hills and the other had a herd of elk calving at the base of the tree when we found it abandoned. Not sure either was the cause of the failure. The most significant act of disturbance that we observed was the result of firewood collectors cutting down a nest tree! The nest was not occupied at the time, but had been improved this season so it was still a relevant resource for the population. In the end, the only management actions that I have recommended to address disturbance is blocking the dead-end ATV trail a bit further from the tree and labeling nest trees to prevent accidental cutting. Both of these have been accepted and will be implemented as soon as we gain access to the area this spring.

Forest Succession:The largest anthropogenic disruption in the South Hills is the disturbance of the fire regime. Humans have been very successful in preventing fire in this natural landscape. The results is that much of the forest, especially Aspen, is the same age with a similar structure. Species diversity in general is dependent upon a mosaic of age classes and structures. Goshawks to date have generally benefited from this action as they prefer late stage forest structure (mature trees with relatively open understory). However, most of the mature Aspen in the South Hills are reaching the end of life. They are regenerating, but these regenerated forests will not be available to goshawks for decades. Most all of the goshawk nest stands that are Aspen are over 50% dead. Hence there is a predicted looming gap between the death of the stands available today and the emergence of new regenerated stands. In a natural fire regime, stand succession would not be synchronized and thus stands would always be available in all of the separate successional stages. The management recommendation here is to not only introduce fire to the habitat, or at least not be so aggressive when extinguishing natural fire, but also to accelerate forest succession through thinning. Thinning a young stand of trees can accelerate the development of that stand into a mature stand by shortening the development time by up to a decade. Thinning is not new in the South Hills; three of the successful nests last year were located in stands which had been thinning during the past decade. Thinning is already within the forest service budget, this just shifts the choice of stands to those that could also benefit goshawk success. Once again, the goal is not to return all stands to mature, but to disrupt the age synchronization currently pervasive in the area.

Aspen stand in transition - unfriendly to goshawks.
Previously thinned Lodgepole Pine stand (open understory) - friendly to goshawks

Prey abundance: One of the reasons that the goshawk is a good local management indicator species is that they are a generalist predator. They are dependent and consume a broad range of species including mammals and birds. Managing the forest for these species usually requires work to increase the health in general. Goshawks do feed heavily on cavity nesting birds such as woodpeckers. Cavity nesting birds are heavily dependent upon diseased, dying, and dead trees. Too often we remove as many dead trees as we can, possibly limiting this resource. I recommended not removing standing dead trees located within or near goshawk nest stands.

The surprising end result is a collection of relatively painless management actions which could help improve the ecosystem services in the South Hills - painless restrictions on a few ATV trails, labeling nest trees to prevent accidental destruction, thinning of some new stands to accelerate forest succession, and leaving standing dead trees in existing stands. We will see what insights my second field season brings. I eagerly await my return to the field.

Monday, March 12, 2012

Restoring Wasteland

Yesterday I joined my Sagebrush Habitat Ecology class on a field trip to help restore a piece of land which has seen its fair share of abuse. This land has been grazed, cleared for agriculture, and left for dead. As with most abandoned land, dead would be better than what actually occurs. When the native plants and animals are removed, the land is quickly overtaken by invasives - most notably cheatgrass, medusahead and tumble mustard.
The land we were working on is part of a private ranch which has been purchased by an individual with a history of restoring lands. They are interested in restoring this portion of the land as both Greater Sage-Grouse and Columbian Sharp-tailed Grouse occupy nearby lands. The hope is that this habitat could one day be occupied by these species which are both in critical need of increased habitat availability.
The restoration project began last fall when the land was cleared. After clearing, an herbicide was applied to kill all annual grasses most of which are invasive. I am usually against herbicides due to the potential impacts on animal life, but cheatgrass has proven immune to most all other methods. Following this treatment the land was seeded with a subspecies of Big Sagebrush which grows well in the area, native bunchgrass, and a variety of forbs. Unfortunately Antelope Bitterbrush, a native member of many sagebrush habitats, does not grow well from seed. Our task today was to plant 2500 Bitterbrush starts.
Patrick drilling holes!
The planting process involves drilling holes with a post hole digger. A few hours on this torture machine will definitely leave a mark. I guess that I will still be feeling it come Wednesday! Even though the herbicide had been applied, invasive grasses are already sprouting in the area.
Dr. Forbey takes a turn.
Two post-hole diggers proved about right to keep up with 12 people burying starts. We averaged about ten holes per minute. The burying process required care with the roots to ensure the tips point down and are not damaged by rocks in the soil. With the strong wind today we had to ensure the roots of the plants did not dry out by keeping them rolled in wet burlap.
One of my masterpieces
Finishing up.
After about 5 hours we planted the 2500th start. What a day.
The crew surrounding our final start.
The crew chief estimates that 80% of our starts will survive. If so, this habitat will be much closer to what the native species in Idaho expect. I hope some day this land will be occupied by a grouse, possibly even a lek. It will take another decade or longer until we will know. Unfortunately, there is a lot more work to do, even on this piece of land. The orange rectangle represents the land we covered today.The remaining cultivated portion is planned for restoration during the next two years. The uncultivated land to the right is a problem as it consists of 100% invasives. I am not sure what can be done with that.
Land covered today.
The remainder of the cultivated land must be restored. But then there is the land above this plot and as far as you can see. Surveying the landscape in all directions, this area is over 95% invasive plants with only a few remnants stands of sagebrush. And then there is the land in the next drainage and beyond. This ranch's restoration costs about $300 an acre when using all volunteer resources. This ranch alone will require over 3 years of volunteer effort to restore. What about the millions of acres in southern Idaho in need of restoration...