Question

Isle Royale SimBio lab model:

Islands in general have fewer species than similar mainland habitats because dispersal limits the distribution of species to those that adapted to colonize off-shore habitats.

a) What was the total number of vertebrate species that colonized Isle Royale?

b) How did each of these species disperse to the island?

Answer 1

Exactly Isle Royale is used for, the entire island is a National Park and does not contain any oaved roads, this means there is no human disturbance on the island except foe 165 milesof hiking trail and one lodge.

• Because of this reason wildlife of Isle Royale flourish, such as moose, bald eagle gray wolves etc.
• Most commomly viewwd mammal life in Isle Royale National park are moose, snowshoes hare, beaver, red fox, red squirrel, as well as river otter.
• In 1948-49 during exceotional cold winter, an ice bridge formed between Canada and Island, allowing a small pack of eastern timber wolves to cross over the river to Isle Royale.
• Different variety of fauna was present in Isle Royale like beavers,mink, otters, foxes, harers, squirres, bat, wolves and moose .
• The moose swan to the island in 1900 and the wolves came on the island in 1940 by crossing an ice bridge from canada.
• Today only 18 species of mammals can be found on Isle Royale, compared to more than 40 on the sourrounding mainland.
• Fewer species means fewer relationships between species Isle Royale has only one large prey species, the moose with one predator, the wolf.

Isle Royale is located in the middle of lake superior, the closest mainland is Minnesota, 14 miles away.

• Fishes and birds can travel the short distance easly and these are far and most abundant wildlife on island.
• Mammals can walk across Lake Superior when it is frozen in the winter, like wolves can cross Lake Superior when it freezes, but other mammals like bear do not swim long distance and are sound asleep through the coldest months.
• More over every living things that arrives on the island must able to survive the harsh winter and can able to reproduce.
• The moose population in the island helped to increase in population of wolves.
• Reaching Isle Royale is so difficult, even mammals that can make a trip rarely.
• The avaliability of food in the island helped the animals to remain in the island.
• The wide variety of flora, including several species of trees, shrubs and flowers are also attracted animals towards the Isle Royale.