Climate Change

Common Name:  Grey wolf, Timber wolf, Mexican wolf, wolf, Arctic wolf, Tundra wolf

Scientific Name: Canis lupus

IUCN classification: least concern

Size:

Height: 61-94 cm

Length: 131-201 cm

Weight: 25-86 kg (55-190 lbs)

Range: Canada, Alaska, northern United States, Europe, Asia between 75^oN and 12^oN

General Information:

The grey wolf lives in remote forest habitats in packs varying in number of individuals. These packs are often made up of a family unit with males leaving the pack near sexual maturity. Only the alpha or dominant male and female of each pack reproduces and all members of the pack help to look after the young. The pack hunts cooperatively, allowing them to take down larger prey than they would as individuals (Mech & Boitani 2008).

Habitat:

The grey wolf was once the worlds’ most widely distributed mammal, until over hunting and habitat destruction pushed their populations out of much of their southern range. Currently the grey wolf is found in remote, forested regions with pack sizes and population sizes varying with region.

Climate Change:

With wolves being so versatile in habitat and prey type it leaves the question of how they will be affected by climate change. Wolves have proven that in regions with greater snow fall pack sizes will increase during the winter months, making the pack more efficient hunters. In the case of global warming, limitations on the amount of snow pack during the winter months will cause these packs to remain at smaller sizes. This variation will show drastically different effects on the ecosystem and the trophic food chain within the wolf’s habitat (Post et al. 1999). In the southern populations limited to no snowfall will cause the abundance of prey organisms to increase. This will have varying affects on the vegetative ecosystem of the area.

One example of this is with the Isle Royal population, which has been well studied for many generations. These wolves prey upon mainly moose in the winter months and with increase in snowfall there is a tripling in the rate of moose take-down. This stops the moose from eating the vegetation and therefore the vegetation in the area benefits. With wolf packs remaining small the moose population will increase and the vegetation will show a decrease due to over browsing (Post et al. 1999).

Another similar impact of wolf populations on ecosystems undergoing climate change has been studied in Yellowstone National Park. There the extirpation and reintroduction of wolves has given scientists the ability to view the impact of the wolf population on the ecosystem. With wolves as one of the top predators in Yellowstone they cause effects on the entire trophic cascade. It is believed that wolves act as a buffer to climate change through their contribution of carcasses and population control. For lower level predators and scavengers winter without wolves meant little to no food was available but with wolves they can survive. In the reintroduction of wolves to the Park, balance has been seen between predators, scavengers and prey. This balance will allow these organisms to feel the effects of climate change to a lesser degree (Wilmers & Getz 2005).

Common Name: North American/ European/Vancouver Island Wolverine

Scientific Name: Gulo gulo sp.

Gulo gulo luscus (North American)

Gulo gulo gulo (European)

Gulo gulo vancouverensis (a possible Vancouver Island sub-species)

IUCN classification: Near Threatened

Size:

Height: 36-45 cm

Length: 65-105 cm

Tail: 13-26 cm

Weight: 9-30 kg (20-66 lbs)

Range: Northern Europe, Asia, North America (boreal zone)

General Information:

Wolverines are known as solitary, aggressive and territorial animals and are one of the largest members of the mustelidae or weasel family, which includes skunks, martins, and ferrets. They are also known for great courage, with individuals known to chase bear, cougar, and wolves from carcasses. Their ability to travel long distances and maintain high rate of speed for approximately 10 miles (16 km), explains why home ranges are so large. With the wolverines range being mainly in the high northern hemisphere these usually nocturnal animals will often experience 24 hour day or night. During these periods their time is spent with four hours of rest followed by four hours of activity (Patsy et al. 2009).

Wolverines are commonly known as scavengers of the kills of other predators such as wolves, cougar, or lynx. Much of their usual hunting prey consists of wild sheep and small mammals, including rodents and lagomorphs. In the winter season Wolverines have been known to hunt larger prey such as deer and moose due to the inability of the prey to maneuver well in deep snow (Abramov 2009).

The mating season of the wolverine is during the summer months, but unusual in this process is the 6-7 month period between insemination and implantation. Implantation occurs in the winter months and kits are born between February and April depending on region. Authorities in this area have not come to a solid conclusion as to the birthing time of the wolverine but kits emerge from under snow dens in April and May (Rausch 1972). Wolverines become sexual mature at approximately 2.5 years old (Whitman 1999).

Habitat:

Wolverines live mainly in boreal forests in the northern hemisphere with their range spreading south through western North America through to California. Historic ranges covered much more of the southern regions of Europe, Russia, and North America. Due to hunting and population fragmentation, as well as habitat destruction they have been limited to more remote regions (Abramov 2009).

Wolverines are territorial with females maintaining smaller ranges than males, territories vary between 100 km² and 600 km² (Whitman 1999). Density of these animals ranges between 1 per 500 km² in northerly regions and 1 per 65 km² in southern regions within the United States (Abramov 2009).

Climate Change:

The Wolverine has a deep connection with the snow causing it to be one to the organisms which will show the effects of climate change. This connection is seen through its scavenging of carcasses which are more easily stored in the cold of winter, as well as in its increase ability to catch and take down prey items in the snow (Abramov 2009). As the snow line creeps higher up the mountains and further north wolverines will be left limited in their hunting ability as well as their scavenging ability. Scavenged carcasses in a warmer climate will decompose at a higher rate decreasing the availability of scavenged food. Also the ability of the wolverine to hunt large prey will become non-existent.

Due to high population fragmentation within the southern ranges and the locality these populations will be the hardest and first hit by climate change with the potential extirpation of these species from these southern regions. The wolverine has already undergone massive habitat destruction and fragmentation and with the impending climate change will surely show massive decrease in range over the next century.

71% of the earth’s surface is occupied by oceans/seas and these oceans and seas are a major component of the carbon cycle and therefore effect climate change. Climate affects ocean mixing, stratification, light levels, and nutrient cycling. Plankton phenology (annual life cycle events) is a sensitive indicator of climate change and is affected in ways such as range shifts, timing, numbers, and subsequent effects on other trophic levels (bottom up interaction). There is a significant correlation between sea surface temperatures and seasonal summer cycles of plankton. There is also a correlation between plankton and water column stratification changes, which can be brought on by climate change.  The intensity of the affects felt by plankton and other subsequent trophic levels (bottom up) differ between the different plankton assemblages.

Krill have decreased ten fold over the last 25 years, (major food for whales and other mammals) due to a decrease in summer phytoplankton blooms and winter ice algae. Range shifts of copepods in warm water assemblages have moved 100km to the north while the cold water assemblages have experienced retractions in range. North Sea phytoplankton blooms have advanced in their timing by weeks compared to their grazers the zooplankton in response to great sea surface temperatures. This disruption of timing has a potential to have a sever impacts on the other trophic levels, (bottom up) and with a mismatch between trophic levels the success of the whole system decreases.

General Facts

Conservational Status: Extinct

Scientific Name: Bufo periglenes

Size: <5cm in length

Range: The Monteverde Rainforests in Costa Rica at elevations only between 1500-1620m above sea level.

Habitat: Tropical and Subtropical Montane forests

Ecology: The Golden Toad was an endemic species to Monteverde Rainforests.  This rainforest is known as a cloud forest because it obtains most of its moisture from the clouds and not precipitation.  The toads burrow underground for most of the year except during the breading season.  The Golden Toad breeding season would begin at the beginning of the wet season; the toads would gather in large numbers at temporary pools in the forest.

Evolution: The Golden toad was discovered in 1966 and became extinct by 1989.  Due to the toads habitat requirements they were geographically isolated.  In 1988, Monteverde rainforest was warmer than normal and the temporary pools dried up before the tadpoles could mature, that led to a significant reduction in adult toad population.  Because the global temperature has continued to rise the pools that the toads had relied on for reproduction are no longer there.  This has significantly contributed to a decline in population.