Niche the Erethizon dorsatum (North American porcupine)
The North American Porcupine uses a variety of habitats, including different elevations and varied climates. They can live in the tundra, forests and desert chaparral. Porcupine habitat varies geographically. In the Pacific Northwest, porcupines remain primarily on the ground. In New York for example, porcupines are mainly tree dwellers. The time porcupines spend on the ground is related to the amount of ground cover that exists for foraging and protection from predators and based upon the density of predators. Porcupines spend their winter in dens, usually rock dens where available or even trees. Different trees are chosen for resting than for feeding. For example in the east, hemlocks are usually chosen over other conifers for both resting and feeding.
Porcupines are generally herbivores and they typically eat leaves; roots and tubers; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers.
They depend on all plant life for survival and Even with their elaborate defense mechanism, porcupines are preyed upon by a couple of co-adapted predators. Several predators exist that at least have been known to kill a porcupine. The list includes lynx, bobcats, coyotes, wolves, wolverines, and great horned owls. Other Important predators include mountain lions and fishers. Porcupine feeding happens primarily at night. This is because of the changes in plant and leaf chemistry at night. Porcupines take advantage of the added nutrients available during the night-time metabolic processes of plants. Interesting facts include the Porcupine's defense mechanism. They have white tipped quills that serve as warning signs for predators and they can release a nasty scent from their quills. Porcupines use their quills in two ways, defensively (as a shield made of barbs) and offensively (when they are driven into the predator).
Factors which Affect Birth Rate of the North American Porcupine
They mate in the months of October and November.
They breed only once a year.
Their gestation period is 205 to 217 days; avg. 210.25 days
One to two offspring are born each pregnancy.
It protects them for about 127 days after birth by feeding them and staying close to them. Slowly, they start to separate and give the porcupine offspring independence.
For females it is 25 months till reproductive maturity and males it is 29 months, they reproduce once year during their life span.
Factors Which Affect the Death Rate of North American Porcupine
The porcupine has a list of predators that feed on it including the bob cat and the great horned owls. Porcupines are herbivores so they do not have predator-prey relationships unless they are the prey.
They can live from 6-18 years in the wild.
Both external parasites such as ticks and fleas, and internal parasites such as round worms and tape warms do not seem to have any effect on porcupines. Yet, they do fall ill to rabbit fever.
Over-population can make ground land scarce and food resources scarce, potentially affecting the animals.
Food Chain of the North American Porcupine Producer Autotroph Primary Consumer Herbivore Secondary Consumer Carnivore Tertiary Consumer Omnivore
Food web of Assigned Organism Herbivore Producer Carnivore Carnivore Carnivore Herbivore Herbivore Omnivore Producer
There is the mark and recapture study which involves capturing individuals from a population of interest, marking them, releasing them for a relatively short period of time, and then later recapturing individuals from the same population and counting the number of marked and unmarked individuals. Estimations can then be made on the populations size.
A population sampling technique used before is the mark and recapture study in which a group of people captured 39 porcupines and monitored 37 of the animals and made estimations on them.
Pertaining to the health of the ecosystem, stream quality can be effected by these different levels because certain levels affect stream quality and the life within the stream.
The ideal range for Ph is 6.5-7.5, nitrates and phosphates are low, and dissolved oxygen is between 10-15 and the possible ramifications for levels outside the ideal range is the stream quality going down and organisms dying.
The Porcupine would thrive if it was near the Powdermill stream because is it good water quality, but if it were around the marsh or mine water the Porcupine could die or have health issues.
Temperature affects dissolved oxygen levels, the colder it is, the more D.O. Turbidity can affect the predator-prey relationships .
The stream water would affect by organism only positively because good water quality can give it good health and good drinking water.
The soil conditions are good, meaning that my organism wouldn’t be negatively affected by the soil. Yet, if the soil was bad, it could hurt the Porcupines health.
Negative factors that would effect the stream would be farmland runoff and acid mine drainage. Positive would be wetlands and limestone treatments that look to help clean the bad quality waters. Poor water quality could affect my organism because it could lead to bad health.