Sunday, March 30, 2008

Trophic Cascades

I have written here on a few occasions my fascination with trophic cascades. "Trophic cascades occur when predators in a food chain suppress the abundance of their prey, thereby releasing the next lower trophic level from predation (or herbivory if the intermediate trophic level is an herbivore)" (

My favorite trophic cascade, which I have described before in this blog, is the role of the Wolf as the Keystone Predator.  In Yellowstone National Park, the return of the Gray Wolf into the ecosystem has caused the Elk to spend less time on the river banks.  This has encouraged more Willow growth, which has in turn encouraged Beaver to return.  In 1995 the Northern range of Yellowstone had only 1 beaver colony, now it has 9.   This in turn should provide more trout habitat, hopefully benefiting some of the endangered species in Yellowstone. Wolves also decreased the coyote population, benefiting coyote prey species such as pronghorn and ground squirrels (see my earlier story on Wolves, Pronghorn, and Coyotes). Its amazing that one species can have such a dramatic effect in the eco-system. This is why the wolf is a Keystone Species.

In my preparation to return to school in the fall, my reading has brought me across some other fascinating trophic cascades.  The first came from Cornell Lab of Ornithology's Handbook of Bird Biology (chapter 9, page 128).  The study presents the relationship of Sapsuckers, swallows, willows, and aspen.  In this environment, the sapsucker, a type of woodpecker, is a keystone species. The conditions must be right to accommodate sapsuckers, but when they are present, the species diversity increases.  The study first demonstrated that the sapsucker preferred to nest in aspen trees that are situated near a certain type of willow, which provides food for the Sapsucker. Additionally, the sapsucker could only bore its nest cavity into the Aspen when a certain type of fungus was present. Thus an Aspen grove with the heartwood fungus, near a willow grove, provided the perfect habitat for the sapsucker. A couple of behaviors of the sapsucker make it a keystone species. First, it drills holes in the willows to get at the sap. These sap wells were visited by numerous other birds, rodents, and bugs that all benefited from the sapsuckers work. The study did not prove that any of these species would be absent without the sapsucker, so this was non-conclusive to grant keystone status to the sapsucker. But another observation was. The sapsuckers bore into the aspen to create their own nest cavity. They seldom use a nest cavity more than once. These nest cavities are used by other cavity nesting birds in subsequent years. The study went on to verify that the cavity nesting birds in the ecosystem were specifically dependent upon the sapsucker for their presence.  That made the sapsucker a keystone species.  Its fascinating that a single bird species, in fact just a few birds, can have so much influence.

The next story comes from a review of some recent research which was posted at the Not Exactly Rocket Science blog call Loss of big mammals breaks alliance between ants and trees. Here the researchers are studying the removal of what appears to be a keystone species. The detailed summary is fascinating, but the high level is that when large mammals eat Acacia trees, the tree appears to recruit a certain species of ant to attack the mammals as they are eating.  In return the tree provides the ants some nectar. It is an example of a mutual symbiotic relationship.  When the researcher fenced off some trees to prevent large mammals from eating the tree an interesting thing occurred.  The tree apparently decreased the nectar it produced for the ants. The specific ant population then decreased. This allowed for two other parasitic ant species to invade and attack the tree. Apparently the original ant species kept these two at bay. When the tree stopped feeding it, it stopped fighting off the other parasitic species.  The result is that neither the tree nor the original ant species were better off. I suspect that if allowed to progress long enough the tree and the ant species would create a new balance.  To me this speaks more to the result of the change (removing large mammals) than the new steady state. We must remember however that most species that go extinct do so as a result of not being able to adapt fast enough to a change in the ecosystem. Thus, it is possible that the Acacia tree must have both large mammals eating it and the presence of a specific ant species to survive. The significance of this story is that the large mammals are in decline in Africa as they are around the world. Primarily as the result of human activity.   The effect is that many more species, such as the acacia tree, are at risk as a result.

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Saturday, March 29, 2008

Mid-life Crisis

The response to a mid-life crisis varies significantly from individual to individual.  Some people have affairs, some buy expensive cars, some take extreme risks in new adventures, some get depressed, etc. I still haven't figured out what my full response will be, but it doesn't likely include any of the most common responses. I did recently take a significant step down at least one path which could be considered under the "mid-life crisis" banner.

A few weeks back I officially applied to Boise State University for a second Bachelors degree in Biology with an emphasis on Ecology. This shouldn't come as a surprise to anyone who regularly reads my blog.  I post very little in the area of my original degrees - Computer Science and Mathematics, while focusing a great deal on birds, wildlife, conservation, evolution, etc. While Hewlett-Packard has been very good to me over the past 20 years, I don't see myself working there for another 20 years. I'm in no particular hurry to leave, but I do feel I should prepare myself for a time when I am no longer employed by the company. I feel the need to pursue activities more in line with my personal interests - environmental and wildlife topics.

I searched a broad range of approaches that would allow me to get started on the degree path while continuing with my full time employment. There appears to be a lack of credible programs available for distance learning in the physical sciences, likely the result of the heavy laboratory requirements for the education. Boise State University rated well during my evaluation for the local convenience, support of evening classes (at least for classes where multiple sessions are offered), some distance learning classes for the base requirements, and a strength in Ornithology (they even have a graduate program in Raptor Biology) which is a potential emphasis area for me should I continue beyond Ecology.

I described my interest to my advisor in exploring macro ecosystem concepts. I am interested in trophic cascade, predator-prey relationships, and interdependent species evolution. These concepts are well represented in the Ecology Emphasis in BSU's Biology program. The program offers significant content in both micro ecology and macro ecology, the later is where I will likely choose most of my electives. If I only take 2 classes at a time it will take 3.5 years to complete the degree, although I might at some point find more time away from work to accelerate my progress. 

My program kicks off in the fall with General Biology lecture and lab. It's offered in a convenient evening time slot with labs immediately following the lectures. I am also looking at completing one of the communications course requirements as most of the other classes I need have General Biology as a prerequisite. I am still working out this part of the schedule.

The real challenge for me now is to relearn how to be successful in college coursework.  While I have had ample continued learning opportunities in my career, it has been over 15 years since I have taken a mid-term or final exam. My role at HP, at least for the last 15 years, has had a broad focus without a lot of attention to detail. I expect the coursework to take me in the opposite direction.  This will likely be a challenge as well.

I am excited to get started on this new endeavor. In preparation I have stepped up my reading of textbooks by reading Cornell Lab of Ornithology's Handbook of Bird Biology and on ecology by reading more of one of my regular blog carnivals Oekologie.

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Monday, March 24, 2008

Bankrupt Advice

The news is packed with talk of foreclosures, recession, inflation, stimulus packages, and most annoying of all, bad advice.

The bad advice isn't from just anyone, but directly from the President of the United States. The advice I am referring to is the encouragement by the President for individuals to spend their tax return checks and "stimulus package" checks to help the economy. 

The lie that is being communicated indirectly if not directly is that by spending the checks the economy will improve, people won't lose their jobs, won't lose their houses, etc. The reality of the situation is quite different. First, the money in the stimulus checks isn't free, it is stolen from our children in the form of more debt. Second, the spending will do little of anything to improve the overall economy. The most it will do is a short term improvement in the economic indexes to make the government look good during an election year. Third, spending the checks will do nothing to improve the situation of the individual.  The exception will be those that have no choice but to spend the money on rising food and energy costs just to survive. The spending clearly isn't going to save an individuals job even if they turn over the entire amount to their company. This is just another bankrupt idea by this president to further bankrupt our country.

If an individual wants to use the money to help themselves, here is my prioritized list of what to do with it: 1) feed the family; 2) pay down debt; 3) invest in education; 4) save it. Not on the list: spend it on things you don't need just to satisfy our president.

Of course, the president delivering this message is no more irresponsible than starting an unjust war, decreasing national security, racking up record amounts of debt, shifting the tax burden away from the rich and onto the poor, destroying our civil liberties, destroying the environment, and slaughtering the values onto which this country was built.

Update 3/27/2008: Two new polls out indicate the the majority of Americans plan to save or pay down debt with their rebate checks. poll says Half of America won't spend their 'stimulus' rebate. CNN/Opinion Research Corp. poll found that 41% of respondents plan to use their rebates to pay off bills, and 32% will put the money in savings.

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Sunday, March 23, 2008

Weekend Bird Photos

The first official weekend of Spring brought some warmer temperatures to the Treasure Valley (Boise River Valley). It was still cool enough the we chose the afternoons for our bike rides, a long road tandem ride with friends on Saturday and our first mountain tandem ride of the year on Sunday! The mornings were spent hiking and birdwatching the Hull's Grove loop, a 3.5 mile loop from our house. We saw the usual birds out and about counting a little over 20 species each morning. The highlight was watching a Sharp-shinned Hawk in a dive chasing a Red-winged Blackbird. He/she was gaining fast as they slipped out of sight behind the trees. He came up empty as a few seconds later he/she was soaring above the trees without the prey. Here are the photos for the weekend.

Male American Kestrel.

Bohemian Waxwings were out again this weekend.

Female Belted Kingfisher Left, joined by male.

Apparently the female wasn't in the mood.

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Saturday, March 15, 2008


Bohemian Waxwings, one of my favorite birds. We came up on these on a walk earlier today.

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Thursday, March 13, 2008

Counting Birds

There has been a long debate among bird watchers as to whether creating lists is the "right" way to be a bird watcher. Some claim that keeping a list causes you to hurry through the species instead of enjoying the behavioral aspects of bird watching. The other side would argue that keeping the list gets them out into the field more in a higher variety of places. As with most debates such as this, it really comes down to personal preference.

I, as an engineer, do appreciate the numbers and have been keeping lists for the past 4 years. I like checking off new species and I enjoy the return of old favorites. I like to track how the species change throughout the year. I also like to have "great birding days" when I see many species in one day. Although my goal for the year lies with a single species. I hope to see a Peregrine Falcon hunting in a stoop.

I also enjoy watching the species in my backyard that really don't change that often.  The Pine Siskins and Goldfinches being the core of the population right now. I like watching the Siskins hang upside down on the thistle feeder until another comes by, lands on the same roost, then pecks the first one on the butt so that it flies off. I like observing the hierarchical displays of aggression within the species. I also like seeing the rare visitor passing through, a Downy Woodpecker that comes by, or the pair of Black-capped Chickadees which probably visit daily while I am away.

Overall I am more of a list guy. Most of my bird watching not in my backyard is performed while hiking between point A and point B.  The result is that I make lists and count, but spend less time observing the details. I do submit these lists into an online database accessible to bird scientists called E-Bird. This database also helps me to keep track of my personal sightings.

To the numbers. My "Life List" currently consists of 367 species. It's not really a life list, instead it is a 4 year list. The list was helped along tremendously last year when we spent 2 weeks in Costa Rica Birdwatching. Costa Rica expanded my life list by a whopping 203 species! Since then I have only added 5 new birds.

E-Bird also provides yearly totals, monthly totals, site totals, and lots of other geeky data analysis. For example, so far this year I have found 53 different species (at least that I could identify).  Here is the list so far:

1 Dark-eyed Junco        Rob Home + ID 12 Jan 2008
2 House Finch       Rob Home + ID 12 Jan 2008
3 Pine Siskin        Rob Home + ID 12 Jan 2008
4 House Sparrow       Rob Home + ID 12 Jan 2008
5 Canada Goose       Barber Pools + ID 12 Jan 2008
6 Common Merganser       Barber Pools + ID 12 Jan 2008
7 Great Blue Heron        Barber Pools + ID 12 Jan 2008
8 Bald Eagle       Barber Pools + ID 12 Jan 2008
9 American Kestrel       Barber Pools + ID 12 Jan 2008
10 Mourning Dove       Barber Pools + ID 12 Jan 2008
11 Black-billed Magpie        Barber Pools + ID 12 Jan 2008
12 European Starling       Barber Pools + ID 12 Jan 2008
13 Common Raven        Barber Pools + ID 12 Jan 2008
14 Northern Flicker       Barber Pools + ID 12 Jan 2008
15 Rock Pigeon       Barber Pools + ID 12 Jan 2008
16 Red-tailed Hawk        Barber Pools + ID 12 Jan 2008
17 Ring-necked Pheasant        Barber Pools + ID 12 Jan 2008
18 Northern Harrier        Barber Pools + ID 12 Jan 2008
19 American Coot        Cascade Reservoir--South + ID 19 Jan 2008
20 American Dipper        Cascade Reservoir--South + ID 19 Jan 2008
21 Common Goldeneye       Cascade Reservoir--South + ID 20 Jan 2008
22 Barrow's Goldeneye       Cascade Reservoir--South + ID 20 Jan 2008
23 Mountain Chickadee        Cascade Reservoir--South + ID 20 Jan 2008
24 Hooded Merganser        Cascade Reservoir--South + ID 20 Jan 2008
25 American Goldfinch        Rob Home + ID 01 Feb 2008
26 California Quail       Sandy Pt./Discovery State Parks + ID 01 Feb 2008
27 Great Gray Owl        Sandy Pt./Discovery State Parks + ID 01 Feb 2008
28 Golden Eagle        Sandy Pt./Discovery State Parks + ID 01 Feb 2008
29 Sharp-shinned Hawk        Sandy Pt./Discovery State Parks + ID 01 Feb 2008
30 Northern Goshawk        Military Reserve + ID 03 Feb 2008
31 Steller's Jay        Military Reserve + ID 03 Feb 2008
32 White-crowned Sparrow       Military Reserve + ID 03 Feb 2008
33 Mallard        Hulls Grove, Boise + ID 09 Feb 2008
34 Red-winged Blackbird       Hulls Grove, Boise + ID 09 Feb 2008
35 American Robin       Hulls Grove, Boise + ID 09 Feb 2008
36 Great Horned Owl        Hulls Grove, Boise + ID 11 Feb 2008
37 American Crow        Hulls Grove, Boise + ID 14 Feb 2008
38 Song Sparrow        Military Reserve + ID 15 Feb 2008
39 Downy Woodpecker       Rob Home + ID 16 Feb 2008
40 Cedar Waxwing        Rob Home + ID 16 Feb 2008
41 Wood Duck        Kathryn Albertson Park + ID 17 Feb 2008
42 Eurasian Wigeon       Kathryn Albertson Park + ID 17 Feb 2008
43 Northern Shoveler        Kathryn Albertson Park + ID 17 Feb 2008
44 American Wigeon       Kathryn Albertson Park + ID 17 Feb 2008
45 Yellow-rumped Warbler        Kathryn Albertson Park + ID 17 Feb 2008
46 Belted Kingfisher       Kathryn Albertson Park + ID 17 Feb 2008
47 Ring-billed Gull       Kathryn Albertson Park + ID 17 Feb 2008
48 Gadwall        Park Center Greenbelt + ID 18 Feb 2008
49 Ring-necked Duck        Park Center Greenbelt + ID 18 Feb 2008
50 Pied-billed Grebe       Park Center Greenbelt + ID 18 Feb 2008
51 Black-capped Chickadee       Park Center Greenbelt + ID 02 Mar 2008
52 Killdeer        Boise + ID 09 Mar 2008
53 Turkey Vulture        Park Center Greenbelt + ID 10 Mar 2008

More data than I know what to do with. Enjoy the birds.

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Saturday, March 08, 2008

Wolves, Pronghorn, and Coyotes

I have often written about the trophic cascade effects of a top predator. Trophic cascade refers to the cascading effects on an ecosystem from the presence of a top predator. It ranges far beyond the direct predator-prey relationship. For example, wolves move elk from the rivers, encouraging more willow and cottonwood growth, benefiting beavers and moose.  Beavers in turn benefit trout by creating more habitat.  The cascade continues.

A new research study just published by the Wildlife Conservation Society provides more data regarding the interdependency of wolves, coyotes, and pronghorn - Are Wolves The Pronghorn's Best Friend? The study measured the pronghorn fawn survival rates in wolf abundant areas and in wolf free areas.  The fawn survival rate in wolf free areas was only 10 percent, while it was 34 percent in wolf abundant areas. The key difference is that wolves keep the coyote population in check. Coyotes, not wolves, prey directly on pronghorn fawns.

It is interesting that the State of Idaho is currently paying money to kill coyotes and will soon launch a money losing proposition to kill wolves. This is all because we feel some inherent need to "manage" wildlife. If history repeats itself, which all indications are that it will, our "management" will result to be more like "meddling" resulting in even more problems.

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Monday, March 03, 2008

Transit Stats and Some Facts About the Cost of Gridlock

In preparation for some upcoming Idaho legislation to enable more options for transit funding, there have been a number of interesting data points shared among the transit community.

The most interesting statistic that I have found so far is the following:

  • If 1 in 10 Americans regularly used public transportation, U.S. reliance on foreign oil could decline by more than 40% or nearly the amount of oil imported from Saudi Arabia each year.

Wow.  This decrease would allow the US to exceed the Kyoto guidelines. This would be very beneficial to our national security, our economy (except the oil companies), decrease our trade deficit, improve air quality. etc.  Another way to accomplish this would be for everyone to use alternative transportation at least 1 incremental day every two weeks. This is not a huge impact on personal convenience.

Other statistics:

  • A rush-hour driver wastes an average of 99 gallons of gasoline a year due to traffic congestion. Ninety-nine gallons @ $3.20/gallon = $316
  • The average cost of lost productivity time in rush hour traffic is $1,160 per person per year.
  • More than 120,000 Treasure Valley (Southwest Idaho) drivers who commute back and forth to work on I-84 can spend from 1-2 hours in gridlock every day (round-trip); commuting time gets worse during bad weather and fatal accidents.
  • The annual cost of driving a single-occupancy vehicle ranges between $4,826 for a small car and $9,685 for a large car, depending on fuel efficiency.
  • An annual bus pass for Boise-area ValleyRide services costs $266. An annual bus pass for ValleyRide’s Intercounty services costs $50/month or $600/year.

To prove that we are heading in the right direction: ValleyRide saw bus ridership on the intercounty service (between Nampa/Caldwell and Boise) soar by 3,000 people (boardings) or 60 percent between July and October in 2007. Proof the gas prices are impacting ridership in the longer length commuter routes.

Sources: Center for Transportation Excellence; Idaho Transportation Department; Valley Regional Transit, Idaho Smart Growth

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