Habitat Fragmentation

Post on 14-May-2015

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Transcript of Habitat Fragmentation

Wildlife - habitat

Term: Habitat Fragmentation

Fragmentation

• Habitats which were once continuous become divided into separate fragments.

• The separate fragments tend to be very small islands isolated from each other by crop land, pasture, pavement, or even barren land.

• Major habitat problem for wildlife in Fauquier County

Fragments

• Population problems

• No immigration or emigration

• Reduced reproductive pool

• Decreasing species diversity

• Increased edge to core ratio

Edge

• At the forest edge, wind and sun light result in dryer conditions than are found in the interior of the forest patch.

• Forest edges are also more accessible to predators and parasites that may occur in adjacent fields or developed areas

• Interior Species can only live in the core of a forest

Arrangement

• Fragments

• Corridors

Wildlife Corridors

• Provide a covered route between fragmented habitats

• Unknown effectiveness

• Low tech best

Riparian Buffersimprove habitat by:

• Functioning as wildlife corridors

• Provides cover for animals to move from one area to another.

Provide cover & edge habitat

• Provides food, cover, & nesting sites

Edge

No edge

• Trees & shrubs provide roosting sites for birds

• Increased humidity provides habitat for amphibians, snakes, & turtles

Shade

• Supplies cover and cool temperatures for fish and aquatic insects

Habitat Requirements of Wildlife

• Food

• Cover

• Water

• Space (Range)

• Arrangement

Food

• Quality & Quantity

• Seasonality– Not just during hunting season

• Supplementation– Plantings– Trees

Cover

– From elements

– From predators

– Edge

Water

• Flowing water

• Standing water

• Dew

• Temperature

• Sedimentation

Space or Range

• Bears: 10 miles

• Crayfish: 2 feet

• Adaptations– Deer will live in a very small range– Bears ranges getting smaller

Niche & Habitat

• Habitat– Place in nature– Where– Biological & physical

resources– Flora & Fauna– Climate– Terrain– Applies to all species

• Niche– Role in nature– What & how– Position in the

foodweb– Physiological &

behavioral adaptations– Unique to each

species

Habitat & Niche work together

• Biological Need:– Female ducks need to supply all fat, minerals

& protein needed in egg w/in 24 hours– Niche:

• Ducks usually eat seeds – lower protein, higher fat• During laying ducks eat invertebrates – high

protein

– Habitat:• Ducks seek shallow wetlands because they warm

quickly in the spring & provide abundant invertebrates

Habitat Project

• Select and describe an ecosystem from the guide

• Describe the management activities needed to create or improve its wildlife habitat

• Include a section on management of invasives• Supplement with management strategies for one

other (non-avian) wildlife species.• Make a powerpoint to display your results.• Have a spokesperson present your management

strategies to the class on Wed.

Habitats

• Agricultural• Grasslands• Shrubland• Forest• Savanna• Wetland• Developed• No more than 2 people per group

Catfish

• Feed fish at 3% of body weight

• Table 4-2 in book, relates length to weight

• 5” = 35.3 lbs/1000

• We have 200, how much do they weigh?

• What is 3% of that?

• How much is that?