The Living Edens: Activities for the Classroom - The Wolf and the Moose
An island population of deer has no predatorsand the the deer population or should predators (wolves) be introduced onto the island? Identify predator/prey relationships and how they. Predation on senescent moose was clustered in one kill zone in the disproportionately kill prey in vulnerable age and condition classes –. .. Peterson RO () Wolf ecology and prey relationships on Isle Royale. Predator & Prey—50 Years of Interdependence Scientists from Michigan will find lesson plans and information about the wolf-moose study at the Isle study of the predator-prey relationship free from outside influences.
The three handouts will be distributed sequentially, not simultaneously. After receiving each handout, the class will be given 15 minutes to read through the material, write out answers to the accompanying questions, and discuss their answers within their learning group.
At that point, one of the groups will be chosen to explain their responses to the rest of the class. Ten minutes will be allocated for each presentation and for a general discussion of any points of contention or confusion. Circulate and listen to student group discussions and guide the discussions by asking questions to deepen thinking, explaining the material on Handout 1, or redirecting discussions that might be going in the wrong direction.
After groups have completed the activity of reading and answering questions, choose one group to explain their answers to the whole class. There can be questions and further points of discussion at this time, but the presentation of Handout 1 should fit into a minute time frame.
Optional resources for student groups can include visuals or samples of tree rings to show tree ring growth patterns. Circulate and assist groups with their discussions during the group work time. Be sure to ask questions about student observations of the graph trends and patterns.
The Wolf and the Moose: Natural Enemies That Need Each Other
After Handout 2 is completed, choose a different group to share their answers with the class. There can be questions and further points of discussion, but the minute time frame should be observed. Optional resources for student groups may include a map of Isle Royale to point out locations where the data on the graph was collected. After Handout 3 is completed, choose a different group to share their answers.
After the last data set on Handout 3 has been discussed, allocate 30 minutes to a final synthesis and an explanation of any follow-up assignments. Thus the total time allocated to this case will be two minute class periods. To complete the final synthesis, student groups should prepare one of the following follow up exercises. Choose one exercise or let students choose, depending on the time available or instructional goals. Write a position paper defending one of four possible conclusions based on the data presented: Reject the primary productivity hypothesis and accept the trophic cascade hypothesis.
Accept the primary productivity hypothesis and reject the trophic cascade hypothesis. Find and evaluate a second article on trophic interactions from the primary literature. Be sure to include the following parameters: What specific hypotheses were evaluated? The wolf-moose project was originally designed to continue for ten years. Administrators of the day suggested that the project end.
Durward found greater merit in continuing to lead these observations. Bythe study in its 22nd year, the moose population had tripled from its original size and then declined to half its maximum size.
During that time, wolves more than doubled to fifty. By now it was apparent. In particular, wolves in were abundant and moose had been on the decline for the better part of a decade. Would it be possible that wolves could drive their prey to extinction? No one had ever observed wolves and their prey long enough to know.
Who Controls Whom on Isle Royale? - SAS
The next two years were dramatic. Wolves plummeted from 50 to Canine parvovirus, a disease inadvertently introduced by humans, was largely to blame for the decline. With only 14 wolves, extinction was a real concern. The only way to know what would happen next would be to continue observing. The wolf population recovered partially during the mids, only to decline again.
For much of a decade wolf abundance remained in the low teens. It seemed plausible, but far from certain, that the low numbers were ultimately the negative consequences of inbreeding. All we knew for sure was that Isle Royale wolves are highly inbred and descended from just a single female and two males. Low wolf abundance provided an unprecedented opportunity — a natural experiment of sorts — to see how moose would respond to reduced wolf predation.
With predation low during the late s and early s, moose lived longer and gave birth to more calves. The moose population nearly tripled to almost 2, by During the winter oflack of forage for the moose, an outbreak of moose ticksand severe winter all conspired against the moose.
The winter had been more severe than any in over a century. The moose population collapsed from its all-time high to just moose. Just as the moose population collapsed, wolves seemed as though they would stage a comeback — their abundance doubled in the mid s.
With the collapse of the moose population, food for wolves was rare, and the timing of their comeback unfortunate. What happened next is something we would not discover ourselves for another 14 years. During the winter ofa wolf from Canada immigrated to Isle Royale. He crossed on an ice bridge that occasionally forms between Isle Royale and Canada. His arrival also explains, in part, why wolves did pretty well from toduring a time when it was relatively difficult for wolves to capture moose.
For several years around the turn of the century, moose seemed to be recovering. Then, a series of very hot summers struck. During hot summers moose feed less, as they spent more time resting in the shade. Having fed less, the undernourished moose were less prepared to survive the winters. Warm temperatures also enabled severe outbreaks of moose tick.
- About The Project: Overview
- The Population Biology of Isle Royale Wolves and Moose: An Overview
Weakened by heat and ticks, moose dropped to their lowest observed levels. Wolves took advantage of weakened moose, fueling high rates of predation.
During the first decade of the 21st century, the moose population steadily slid to its lowest levels. The wolf population, with 30 individuals living in three packs, had been thriving until But with moose becoming increasingly rare, capturing food become increasingly difficult.
One wolf pack failed after another. Bythe population was reduced to 9 wolves living in one pack and another half dozen wolves, the socially disorganized remnants of Middle Pack.
Wolf Ecology and Prey Relationships on Isle Royale (Chapter 4)
DNA analysis of wolf scats collected at kill sites indicates no more than two adult females in the population. If they were to die before giving birth to new females, the wolves would be committed to extinction. One of the important lessons The wolves and moose of Isle Royale have been of interest for so long because they offer some very important, general lessons.
Here is one of the most important. Important attitudes about how we should relate to Nature, and some of our abusive relationships with Nature, are rooted in convictions that we understand Nature well, and can accurately predict how Nature will respond to our actions. For 50 years, the focused purpose of the Isle Royale wolf-moose project has been to predict and understand a relatively simple natural system. But the more we studied, the more we came to realize how poor our previous explanations had been.