Transcript Survival Strategies for Plants and Animals

Survival Strategies for
Plants and Animals
Peter Marchand
Founder of the Winter Ecology
classes at the College level.
“Life in the Cold”
Premier researcher and teacher of
Winter Animal/Plant Adaptations.
Three Options for Overwintering
Success
• Migration
• Hibernation
• Resistance
Migration
• The instinctive
seasonal movement of
animals.
• Ex. = birds, whales,
elk.
Resistance
• Animals and plants
develop strategies to
live in the cold.
• Special characteristics
and adaptations.
Musk Ox
Resistance Examples
• Evergreens - push
water into
extracellular spaces.
• Prevents freezing and
bursting of living
cells.
• Ice crystals can then
form between cells.
Resistance (cont.)
• Maple Trees
– Transfer sugar water to
the roots in the winter.
– Travels back up in the
spring to provide
energy for bud
development.
Resistance (cont.)
• Spruce Grouse - has
extra scales to hold
onto icy branches.
• Caribou, snowshoe
hare, lynx - large feet.
• Ptarmigans - feathers
covering feet.
Resistance (cont.)
• Lynx
– large feet,
act like
snowshoes.
– Can keep up
with prey
better.
Resistance (cont)
Wolverine in winter.
Resistance (cont.)
• Porcupines
– more quills to trap heat
in quills, close to body.
– Strip trees of bark.
Hibernation
• Inactive, sleeplike state.
• Why?
Cold Prevention
Reduce the need for food
• Symptoms:
– Body temp. lowered
– heartbeat lowered
– breathing lowered
(Reducing Metabolism)
Hibernation
• Requirements:
– Need very little energy.
– Need very little oxygen.
“Trigger” :
Hypothalamus- part of the
brain.
Adrenal Gland - located on top
of kidney.
Hibernation
• Black Bear in Den.
Hibernation
• Black Bear
Hibernation
• Homeotherms
– Warm blooded
– Energy reserves:
• respiration
• periodic arousal
– All hibernating
mammals arouse
periodically and body
temp’s change.
Hibernation
• Poikilotherms
– “cold blooded”
– seek underground
burrows.
– Ex’s:
• Snakes, frogs, toads,
salamanders, turtles.
(frogs, toads, sal., turt.
Will burrow in soft mud
near streams and lake
bottoms)
Overwintering success of reptiles and amphibians is best
assured by avoiding subfreezing temp’s.
Reptiles and Amphibians
• Wood frogs – hibernates just below surface
and freezes solid
– Produce glycogen which is stored in the liver
then when they start to freeze it is converted to
glucose and cells are filled with the glucose
(acts like an antifreeze)
• Turtles shift from breathing Oxygen to
osmosis
Types of Hibernation
• 1. True
– Warm blooded animals
• Bats, squirrels, hamsters, swifts.
– Body temp. reaches temp’s close to surrounding
air.
– Arouse themselves to keep warm.
Types of Hibernation
• 2. Pupa
– Cold Blooded animals
– Insects
– Larvae and grubs
• in Galls, Dead leaves, Rotting wood.
Types of Hibernation
• 3. Carnivorean Lethargy
– Bears, Skunks, Opposums
– Body Temp. doesn’t drop much (88 F)
• Don’t lose as much body heat.
– Heart rate drops 40%
Types of Hibernation
• 4. Diurnal Torpidity
– Bats
• active at night
• dormant- day
– Hummingbirds
• active- day
• dormant- night
Types of Hibernation
• 5. Diapause
– Insects
• Find sheltered places to stay away from freezing
temps. And elements.
Fatness and Hibernation
• 1. Fattest animals remain dormant the
longest.
• 2. Species that fatten up early will
hibernate sooner.
Migration
MIGRATION
• The instinctual
movement of animals.
• Animals are
specialized and must
migrate.
• Migrate by air, water,
land.
Migration Routes
• Elk migrating through
Greater Yellowstone
Area.
• Mississippi Flyway for
waterfowl.
• Whales along West
Coast of N.A.
Migration CONS
• Energy cost is HIGH
• Must build up 50% of
body weight as fat.
• Flying over water
• Hunting for waterfowl
• Once south/north:
– New Parasites, diseases,
predators, and food.
Migration: TRAVEL
• Easier by AIR than by
LAND.
• Mammals expend 10x
Energy by running
than a bird of SAME
WT flying same
distance.
• Water travel (Whales),
Energy cost is LOW.
Migration: Breeding Grounds
• Northern Hemisphere
– shift from northern
breeding grounds to a
southern non-breeding
ground.
– Breeding grounds have
more/better resources
for caring for young.
– Practically NO species
is known to breed in
both areas it inhabits.
Migration: Navigation
• Instinctual movement.
• Mapping of landmarks
(learned)
• Some direct themselves
by sun (Own compass)
• Triggered by weather,
seasons, winds.
Migration: Navigation
• Groups migrate
together.
– By air, water, and land.
– Herds of Elk
– Flocks of Birds
– Pods of Whales
– LOST? . . . . . . .