EAB found in five more southern Iowa counties -- Read more here!

Balancing Act with Predators

The sequence of energy moving from producer (plant) to consumer (insectivore, herbivore, and carnivore) to decomposer is a food chain. A food chain can also be described as a system of organisms each dependent on the previous as a source of food. This concept is important in understanding the energy and food relationships of those in the food chain. Many food chains weave and cross paths to form a food web.

A food web is a network of food chains or feeding relationships by which energy and nutrients are passed from one living organism to another. Food webs are always changing. The balance between predator, prey, and the prey’s food is ever-changing. This balance is impacted by the population of each member of the food web, the richness or diversity in the food web members, the quantity and quality of habitat and the availability of the components of habitat, plus seasonal variability. Limiting factors will also impact the viability of the food web through animal or plant disease, extreme weather patterns that cause drought, flooding, or fire, plus animal-human interactions. Any of these limiting factors impact can impact one organism in the food web and the ripple effect will impact all organisms!

Raptors as a top predator

Let’s look at raptors in the food web, with the red-tailed hawk being the top or apex predator. You can also think of a food web as a balancing act in the shape of a pyramid.

  • The top of the pyramid is the predator, the hawk.
  • The middle of the pyramid is the prey species -- ground squirrel, snake, and rabbit.
  • The base of the pyramid is habitat.

A food web model offers a very simplistic picture of the relationships between each member of that web.

If you remove the predators at the top of the pyramid, will there be more room for prey in the middle? No. But removing a predator could temporarily allow a higher survival of more young, old, or sick individuals. Temporarily is the key word. What happens if you try to squeeze another rabbit block into the prey level of the pyramid? The addition puts the pyramid out of balance - something will crash.

This illustrates how prey species can "eat themselves out of house and home" and may cause population crashes. The habitat can support only a limited number of rabbits. This is the habitat's carrying capacity for rabbits.

Predators keep prey in balance at or near the carrying capacity of their habitat. Without a balancing predator, prey populations can go through huge number fluctuations and can cause an unpredictable chain reaction of events.

Here's some possible reactions.

  • Mice are the main ingredient in a red-tailed hawk's diet. Rodents have an amazing reproductive potential. With an average litter size of eight and becoming mature at eight weeks, two mice can turn into more than 2,000 in only six months. This can happen only when all limiting factors are removed.
  • What might happen if rodents were temporarily out of balance? More rodents could compete with game birds and other animals for a limited food supply of seeds, especially in the winter.
  • What might happen if egg predators like snakes and ground squirrels were temporarily out of balance? Ground-nesting birds could experience a higher rate of egg loss. They may need to make more re-nesting attempts or they might not have a successful brood.

What could you do to the pyramid if you wanted to increase the number of prey animals in the middle (rabbits, etc.) AND keep the pyramid stable and balanced, avoiding any undesirable chain reactions? The answer is to expand the habitat base, keeping the predators in place. With a larger base, more prey can be added and more predators too - to keep the balance.

Wolves and Yellowstone

Yellowstone National Park

After being absent from the greater Yellowstone ecosystem for 70 years, a wolf reintroduction program began in 1995. Putting the wolves back in the ecosystem, started to reduce elk numbers and changed the behavior of the elk. The elk moved out of the valley to be more in the safety of the trees. As the elk spent less time in the valley browsing aspens and cottonwoods, the young trees could grow. More trees stabilized the rivers and creeks. Then the beaver moved in and built dams and slowed the water.  The transformation is amazing. Watch this 4:30 minute video to get the synopsis of how Yellowstone has been changed in the last 20 years. From this video’s description: “NOTE: There are "elk" pictured in this video when the narrator is referring to "deer." This is because the narrator is British and the British word for "elk" is "red deer" or "deer" for short. The scientific report this is based on refers to elk so we wanted to be accurate with the truth of the story.

YouTube Video

But it’s not just wolves in Yellowstone that are making an impact to improve habitat. ReadYellowstone Ecosystem NeedsWolves and Willows, Elk and...Beavers?” where scientists make the connection between beaver and wolves.

Carve out an hour and watch “Leave it to Beavers” episode from the PBS show Nature.

An ecosystem really is a balancing act where all the parts must be in the correct number and location. A quote from Aldo Leopold says it best, If the land mechanism as a whole is good then every part is good, whether we understand it or not...To keep every cog and wheel is the first precaution of intelligent tinkering.”

For decades, folks have lived on the land, but not with the land simply because we have not understood all the parts. Living with the land is much different and is really a shift in thinking. The conservation ethic that Aldo Leopold wrote about in “A Sand County Almanac” is likely an influence on the wildlife biologists and researchers working to restore ecosystems like Yellowstone. To learn more about Aldo Leopold, watch this trailer from The Green Fire Film Project.

YouTube Video

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Upcoming Programs and Opportunities

Minnesota Avian Adventure - January 16-19, 2015
Carroll, Cass, and Sac County Conservation Boards have teamed up to offer another exciting trip north! We will be heading to Sax-Zim Bog, Two Harbors, and Duluth, with many stops in between. This isn't just a birding trip, it's a trip to see lots of other wildlife, explore the beautiful North Woods and scenic Lake Superior coast, take in the quaint culture of the area, and to have a fantastic time with like-minded souls. Registration cut-off December 31, 2014.  For more details download this pdf!

Teacher professional development opportunity!
Helping Students Protect the Environment and Live Well - 1 hour graduate credit eLearning course - Explore with your K-8 students* the products Americans use daily—“the stuff of life.” These products have a life cycle: They are extracted, transported, produced, used and disposed of around the globe—including in Iowa. Study how this “stuff” is a primary source of environmental problems and examine how this relates to life satisfaction. Then, identify individual and collective actions to address these challenges. Course content is real and relevant; materials introduced are interdisciplinary and classroom-ready and are designed so your students learn Iowa Core and NGSS essential skills and concepts. One-hour of graduate or undergraduate credit. Starts January 5, 2015.

Free online course about Aldo Leopold!
Have you heard of a MOOC? It stands for Massive Open Online Course, and the University of Wisconsin-Madison is hosting one this winter called "The Land Ethic Reclaimed: Perceptive Hunting, Aldo Leopold and Conservation." The three week online course begins on January 26, and there is no registration fee to participate. The course leaders say that all learners are encouraged and welcome to participate, whether they are active hunters, hunting-curious, or simply nature enthusiasts. The course will provide students with an understanding of the historical legacy of wildlife management and recreational hunting as a part of conservation, the role of wildlife in ecosystems, the importance of ethics in guiding management decisions and hunter choices, and the politics and economics of controversies surrounding game and non-game management, hunting, and conservation. Click here to learn more and register!

January 10, 2015
  Bald Eagle Day, Ottumwa, Bridgeview Center
February 14, 2015    Bald Eagle Day, Des Moines Park & Rec, Fellowship Baptist Church, 1503 SE 6th St, Des Moines, 10:00 a.m. to 3:00 p.m. 
March 6-8, 2015    Iowa Deer Classic 

In the news...

Raptor Viewing Etiquette

We should all observe good raptor  viewing etiquette, not only during the nesting season, but also during this time of migration. 

Remember that raptors are protected under the Migratory Bird Treaty Act and bald and golden eagles have additional protections under the Bald and Golden Eagle Protection Act.

Seeing Nature

You can know the name of a bird in all the languages of the world, but when you’re finished, you’ll know absolutely nothing whatsoever about the bird... so let’s look at the bird and see what it’s doing  That’s what counts! 

I learned very early on the difference between knowing the name of something and knowing something. ~Richard Feynman, physicist

YouTube Video

Winged Expressions!
Check out the new sculpture near the 'entrance' to Horn's Ferry Bridge!

Horn's Ferry Bridge

Who Am I? for the week of 15 December

Mystery Critter #83 

So, let’s get down to it. Put on those thinking caps, grab your friends and family, and let’s play Mystery Critter! And remember — no cheating!
    • I am primarily nocturnal,
    • I am brown,
    • I can be found in most of Canada and the US,
    • I breed once a year, and
    • My predators include the Gray Wolf and Bobcats.
What am I? Make your guess, and then go here for the answer and more interesting facts.
Did you get it right?! If not, no worries — you’ll have another chance next week!

Thanks to The Grass Stain Guru for giving us permission to re-post past "mystery critter" posts here on this site! As a hint, we'll only pick out the "mysteries" that can be found in Iowa.

emerald ash borer

Emerald Ash Borer state-wide quarantine announced

Emerald Ash Borer Confirmed in Five Southern Iowa Counties

Larvae discovered in Appanoose, Lucas, Mahaska, Marion, and Monroe counties; brings total to eighteen counties with confirmed infestations

DES MOINES – Emerald Ash Borer (EAB) has been positively identified in Appanoose, Lucas, Mahaska, Marion and Monroe counties in southern Iowa. EAB kills all ash tree species and is considered to be one of the most destructive tree pests ever seen in North America.

The discovery of this series of infestations started when forestry contractor found many dead ash trees with heavy woodpecker flecking while completing a timber stand improvement project on privately-owned woodland on the far eastern edge of Lucas County. The infestation appears to have been in place for several years. The larvae were located only 3/8 of a mile from Monroe County. EAB team members continued to examine trees in the area and additional larvae were found in ash tree on public property in Monroe County, near the Lucas site.

In Marion County larvae were found in a heavily-flecked ash tree on State property on the edge of Marysville. In Appanoose County larvae were found in a tree along train tracks in Moravia. And, in Mahaska County larvae were collected from a tree on private property on the north side of Eddyville.

Eighteen Iowa counties now have confirmed EAB infestations. A statewide quarantine, issued on Feb. 4, 2014, remains in place and restricting the movement of hardwood firewood, ash logs, wood chips and ash tree nursery stock out of Iowa into non-quarantined areas of other states.

“Woodpecker-flecked ash trees are a great calling card when investigating an insect infestation. The damage symptoms on ash trees are very visible during the winter months. Woodpeckers feed on more than EAB, but when we find woodpeckers focusing on ash trees in an area, it’s a red flag that begs for further investigation,” said State Entomologist Robin Pruisner of the Iowa Department of Agriculture and Land Stewardship.

“We urge Iowans to be vigilant, reporting suspicious symptoms in Counties that are not yet known to be infested to a member of the Iowa EAB Team. And we continue to urge citizens to keep firewood local, don’t pack a pest to a new area,” said Mike Kintner, IDALS EAB and Gypsy Moth Coordinator.

The Iowa EAB Team provides EAB diagnostic assistance to landowners and includes officials from Iowa Department of Agriculture and Land Stewardship (IDALS), Iowa State University Extension and Outreach, the Iowa Department of Natural Resources (DNR), USDA Animal Plant Health Inspection Service and the USDA Forest Service.

The Iowa EAB Team strongly cautions Iowans not to transport firewood across county or state lines, since the movement of firewood throughout Iowa or to other states poses the greatest threat to quickly spread EAB and other plant pests. Most EAB infestations in the United States have been started by people unknowingly moving infested firewood, nursery plants or sawmill logs. The adult beetle also can fly short distances, approximately 2 to 5 miles.

The next window for preventive treatment measures (trunk injection, soil injection, soil drench, or basal trunk sprays) will open early spring 2015 (mid-April to mid-May). If a landowner is interested in protecting a valuable and healthy ash tree within 15 miles of a known infestation, they should use the winter months to have landscape and tree service companies bid on work, and these bids can be reviewed before next spring.

Please contact Iowa EAB Team members to have suspicious looking trees checked in counties not currently known to be infested. The State of Iowa will continue to track the movement of EAB on a county-by-county basis. Before a county can be officially recognized as infested, proof of a reproducing population is needed and an EAB must be collected and verified by USDA entomologists.

To learn more about EAB and other pests that are threatening Iowa’s tree population, please visit www.IowaTreePests.com.


Three cameras are placed below the Lake Red Rock dam, one pointed to the dam, one to the river, and one downstream towards Horns Ferry  Bridge. We only see one camera view at a time. Each camera also digital zoom, but there is no IR (infra-red) camera to provide night video.

**There can be technical difficulties with the camera as the feed is at the end of the DSL line and doesn't always have the speed/capacity for good viewing.  Thank you for being patient.

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Check these out!

Iowa Young Birders - Check out this group formed in 2011 to help young people experience the joy and wonder of finding, seeing, and identifying birds!  The Iowa Ornithologists Union is helping to sponsor birding field trips for young people age 8-18 in conjunction with their spring and fall meetings. Check out the details and the Iowa Young Birders website for other field trip opportunities! <jealous!>

Healthy and Happy Outdoors - Learn more about this new Iowa Department of Natural Resources initiative here. Register with the program and record your outdoor activities in Iowa parks and recreation areas with each recorded activity a chance to win outdoor gear in a drawing.  The site also has a search feature for finding outdoor activities in Iowa.

Visit MyCountyParks.com to check out a park or wildlife area you might want to explore managed by one of Iowa's 99 county conservation boards! Look here for events and activities, too!