Transcript Biodiversity PowerPoint presentation

Aren't the Broads Brilliant !
Biodiversity:
Winners and Losers
The
Broads
A member of
The National Park
family
Roman times
Today
© Mike Page
Created by drainage
and peat digging
© Mike Page
Biodiversity
> 11,000 species
> 1,500 of conservation
concern
65 depend on the Broads
5 species lost per decade
Our environment is changing
Potential flooding
Pressures
•
•
•
•
Pressures
• Hotter drier summers
• Warmer, wetter winters
• Sea level rise
• Extreme weather events –
frequency and intensity
Examples
• Migratory birds not
arriving from Africa
(cuckoo, nightingale)
• Plants affected by
drought - habitats
change
Examples
• 15 species of
butterflies have
spread since
1970s
• They appear
earlier and have
an extra
generation during
the summer
How to adapt ?
• Those species most suited to the new
environment will flourish.
• E.g. If salt water incursions increase and the
Broads becomes more brackish, sensitive
freshwater fish species will be killed.
But brackish water species will flourish
Workshop Top Tips
Features that may allow / prevent adaptation
• What habitats do the species live in?
– Fresh / salt / brackish water
– Restricted / rare habitats
– Generalists (species that occur in many habitats)
• Will this habitat be affected by climate
change?
– Drying out / flooding
– More salt water
• Will their food or predators be affected?
Your Task
• Using the resources provided, and your own knowledge and
judgement, decide how the species populations will respond
to climate change, in terms of distribution and abundance.
• 3 groups, each group will have 5 species
• Each species may be winner or loser as a result of climate
change
1. Research each species, decide how it may be affected by
climate change
2. Imagine climate change has happened (100 years in future)
3. Consider where it might be found in the Broads
Species to find out about:
Group 1
Fen orchid
Brown rat
Water lily
Seaweed
(eel grass)
Otter
Group 2
Herring gull
Grey seal
Eel
Natterjack toad
Bittern
Group 3
Little egret
Fen raft spider
Bats
Swallowtail
butterfly
Tentacled
lagoon worm
• Don’t go on to the next slides until the groups
have had a chance to think and do the task.
The results
Winners
•Brown rat
•Herring gull
•Little egret
•Grey seal ?
•Seaweed – eel grass?
•Tentacled lagoon
worm ?
•Otter ?
•Eel ?
Losers
• Swallowtail butterfly
•Fen orchid
•Fen raft spider
•Natterjack toad
•Water lily ?
•Bittern?
•Bats ?
The next 3 slides summarise possible impacts
to help work out the winners and losers ...
Group 1
Winner
or loser?
Fen orchid
L
Brown rat
W
Water lily
?L
Seaweed – eel ?W
grass
Otter
?W
Fragile population - needs clean calcareous water
Threatened by:
• drought
• increased acid rain
• inundation from polluted water or sea water
• lack of management
Very adaptable to different conditions
Eats a wide variety of food
Can breed rapidly when conditions are right
Needs pretty good water quality
Can cope with range of water depths but not floods
Cannot cope with salty conditions
Needs salt water and tidal water
Could expand rapidly if conditions right
Prone to pollution/ too much nutrient
Local populations thrive in freshwater though
elsewhere in the UK they live on the coast
Needs clean water and can cope with variable levels
Eats various prey but needs healthy populations.
Group 2
Winner
or loser?
Herring gull
W
Grey seal
?W
Eel
?W
Natterjack
toad
L
Bittern
?L
Associated with the sea, but now moving inland
Able to eat a wide variety of prey (and scavenge)
Nest in a variety of locations
Being able to fly they can escape adverse conditions
Live in salt water and need good prey levels
If sea levels continue to rise, more water will become
salty giving new opportunities
Young - born in winter - vulnerable to more storms
Start life in the sea and move to freshwater and
wetlands as they grow
Often move to new areas in times of floods
Eat various prey but need clear passage to/fr the sea
Very specialised - lives in wet areas that tend to dry out
Can’t compete with other toads and therefore has
restricted conditions
Variable rainfall and salt inundation will kill them off
Can have masses of offspring if right conditions exist
Need large areas of undisturbed reedbed and
freshwater; Vulnerable to changing water levels
flooding out the nest and losing that year’s youngster.
Group 3
Winner
or loser?
Little egret
W
Fen raft
spider
L
Bats
?L
Swallowtail
butterfly
L
Tentacled
?W
lagoon worm
Spreading through England from the south v possibly
linked to warming conditions
Can find prey in fresh and salt water
Can fly away from adverse conditions
Highly specialised spider - needs good quality,
calcareous water with associated plants
Susceptible to flooding and salt water
Drought conditions restrict them
Bats hibernate so longer periods of warmer weather
could increase insect numbers and so help them
Drought conditions generally restrict insects
Flooding is difficult for them - tho they can fly away
Needs milk parsley for their caterpillars - this is
restricted to suitable freshwater fens (vulnerable to salt
water incursion and flooding and drought)
Can fly away but limited by lack of suitable wetlands
Tiny bristle worm lives in mud tubes in estuaries
Seems to need brackish conditions
Can’t tolerate too much salt or pollution or changes in
currents. More brackish conditions are likely, but the
currents or too much salt might not help