Related Experiment Video
Updated: Mar 6, 2026
09:09
Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
Published on: August 8, 2017
8.1K
Diet shifts in moose due to predator avoidance.
1Biology Department, Williams College, 01267, Williamstown, MA, USA.
Oecologia
|March 18, 2017
Summary
Moose cows with calves on Isle Royale avoid wolves by staying on islands, sacrificing a high-quality diet. This predator avoidance impacts moose foraging behavior and population dynamics.
Area of Science:
- Ecology
- Wildlife Biology
- Behavioral Ecology
Background:
- Moose populations on Isle Royale exhibit distinct behaviors based on reproductive status.
- Predator-prey dynamics, specifically wolf-predation on moose, are a key factor influencing island ecosystems.
Purpose of the Study:
- To investigate how reproductive status (calves vs. solitary adults) affects moose distribution and diet in relation to wolf presence.
- To understand the indirect effects of predators on prey foraging behavior and diet quality.
Main Methods:
- Observational study comparing the distribution and diet of moose cows with calves versus solitary adult and yearling moose.
- Analysis of plant phenology and nutrient availability across different island habitats.
- Dietary analysis comparing plant selection and preference between different moose groups.
Main Results:
- Moose cows with calves remained on predator-free islands, deviating from the typical foraging pattern of solitary moose.
- Cows with calves consumed a lower quality diet, including fewer preferred shrubs and more herbs, throughout the growing season.
- Solitary moose utilized higher nutrient areas on the main island, taking advantage of early-leafing plants.
Conclusions:
- Moose cows with calves prioritize predator avoidance over optimal nutrition, impacting their reproductive success.
- Wolves indirectly influence moose populations by altering their foraging behavior and diet composition.
- Predator-prey interactions have significant cascading effects on ecosystem dynamics and prey population growth.
More Related Videos
Related Concept Videos
02:39Predator-Prey Interactions
22.0K
Predators consume prey for energy. Predators that acquire prey and prey that avoid predation both increase their chances of survival and reproduction (i.e., fitness). Routine predator-prey interactions elicit mutual adaptations that improve predator offenses, such as claws, teeth, and speed, as well as prey defenses, including crypsis, aposematism, and mimicry. Thus, predator-prey interactions resemble an evolutionary arms race.
22.0K
00:48Optimal Foraging
14.1K
How animals obtain and eat their food is called foraging behavior. Foraging can include searching for plants and hunting for prey and depends on the species and environment.
14.1K
00:53Migration
9.0K
Migration is long-range, seasonal movement from one region or habitat to another. This common strategy, carried out by many different organisms around the world, is an adaptive response that typically corresponds to changes in an organism’s environment, like resource availability or climate. Migrations can involve huge groups of thousands of animals as well as single individuals traveling alone and can range from thousands of kilometers to just a few hundred meters.
9.0K
01:05Instinctive Drift
997
Instinctive drift refers to the tendency of animals to revert to their innate behaviors despite repeated reinforcement. Breland and Breland demonstrated this concept in an experiment with a raccoon. The raccoon was trained to pick up two coins and place them in a container in exchange for food. Initially, the raccoon learned to associate the coins with food, making them a conditioned stimulus or a substitute for food. However, over time, the raccoon became less willing to put the coins into the...
997
01:32What is Natural Selection?
131.3K
Natural selection is an evolutionary process in which individuals with survival-promoting traits reproduce at higher rates. These favorable traits become more common within a population or species. Naturally selected traits initially arise via random genetic mutations. In order for selection to occur, there must be variation within a population, the trait controlling the variation must be heritable, and there must be an evolutionary advantage for variation in the trait.
131.3K
01:21Frequency-dependent Selection
24.4K
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.
24.4K