II. Biodiversity – The Problems

Copyright Richard S. Feldman, Ph.D.

Extinction

• Natural and ongoing

– Fossil record

– Background rates

• 1 terrestrial vertebrate species per century

– Local regionalnationalglobal

• So why be concerned?

Concept:

The loss of biodiversity is widespread

and accelerating

–multiple causes

–dire consequences

Endangered and threatened species

a wide

range of

taxa

Decreases "in biodiversity due to human

activities were more rapid in the past 50 years

than at any time in human history…"

Millennium Ecosystem Assessment, 2005

Worldwide threats with extinction

among vertebrates:

• 12% of bird species

• 21% of fish species

• 26% of mammals*

– 50% of primates

• > 33% of amphibians

– 25-45,000 times the background extinction rate

(Center for Biological Diversity, 2015

* IUCN Red List, 2015)

Red List Index for bird species in biogeographic regions

(Birdlife, 2007)

www.ec.gc.ca

Mammals threatened with extinction

April 2015; data from IUCN Red List

and the World Bank

/

http://www.sciencealert.com/this-map-shows-where-

the-most-threatened-mammals-are-in-the-world

Native species extinctions in the U.S.

Presumed extinct: loss of last known individuals is documented;

possibly extinct: no recent documentation of existence.(Stein et al.)

Percent of species at risk of extinction.

Includes critically imperiled, imperiled & vulnerable species From: Stein et al.

Multiple causes

1. Habitat Loss

Concept:

As species lose their habitats, their chances of

survival in the wild are greatly reduced.

http://lal.cas.psu.edu/Research/Images/sprawlComp.jpg

nksandeep.wordpress.com

Terrestrial:

conversion of vast areas of forest,

grass and shrub lands, and wetlands

for agriculture and urbanization

Freshwater:

extensive alterations of rivers,

streams and lakes; wetlands

drained and filled

Loss of tropical rainforests

estimated

original

2010

Amazon tropical rain forest

~20% cut

Amazon

http://rainforests.mongabay.com/amazon/amazon_destruction.html

roads are the critical catalyst for

deforestation

http://rainforests.mongabay.com/amazon/amazon_destruction.html

Primary causes of Amazon

deforestation

1. relocation of urban population

2. government control almost nonexistent

3. cleared areas often productive for only a

year or two (related to TRF paradox)

4. soybean exports

5. cattle ranches (Fig. 6.17).

Fig. 6.17. Increase in gross deforestation (1990-2001) and cattle herd size

(1990-2002) in the Amazon. Each point represents a Brazilian state.

Amazon cattle

• large export market of inexpensive beef

• powerful sector in Brazil

– overrides efforts to reduce deforestation.

– improvements during 2005-2009, led by former

Pres. da Silva,

• cutting limits on farms, enforcement improved

– however, counterbalanced by recent influx of

small landowners – slash & burn

Regional US example:

Karner blue butterfly

Federally & NYS listed endangered species

prairieecosystems.pbwiki.com/Endangered+Karne...

Karner blue

• original range - Maine to Minnesota

– Specializes feeding upon lupine

• Fire-dependent plant species

(www.fs.fed.us/r10/tongass/districts/petersburg/images/lupine.jpg)

• NY: one population in Albany Pine Bush

– 10,000 ha reduced to 1000 ha

– sprawl - cities and suburbs spreading outward

2. Species Invasions

Concept:

Species not native to an area can suppress or

eliminate native species decreased biodiversity.

: charmeck.org/stormwater/PollutionPrevention/Pages/InvasivePlants.aspx myanimalblog.wordpress.com/.../yellow-mongoose/

kudzu mongoose

Introduced species, non-native,

aliens, and exotics

• Synonymous terms

• Species that arrived recently

U.S. ~ 50,000 alien species

• costs $137 billon annually from damage,

losses and control of them.

Subcategory:

highly invasive species

• well-adapted to the physical conditions

• increase rapidly over time and space

• exclude many native species from their

habitats, via:

– competition

– predation

– herbivory

– infection & parasitism

Japanese knotweed in Fern Tor,

Marist College

Intentional introductions –

examples?

• Gardening/landscaping

• Farming

• Pest control

• Forestry

• Aquaculture

Accidental introductions – how?

• more movement of people and goods

between biomes and countries

• crates

• soil

• ballast water

Zebra mussels

• present in

Hudson River

and other NY

freshwaters

Z. mussels

• adults grow on any hard surface

– man-made

– natural – including on other species

• loss of food and habitat for other species

– native mussels threatened

• ~$100 million damage/yr related to control.

Nile perch in Lake Victoria, Africa

• intentional introductions

• voracious predators

• eliminated much of the incredible diversity

in 30 years

vs. ~750,000 years to evolve

www.african-angler.co.uk/fishing.html

Hawaii's native birds

• 1893 – 102 native endemic species

• now - 71 extinct, 31 endangered

• Evolved without any mammalian predators

– Polynesian and European spp introduced

– https://www.youtube.com/watch?v=JLarD5vhd

Kk

Forest pests

• Asian long-horned beetle

• Emerald ash borer

3. Climate Change

Concept:

Species evolved under particular climates,

therefore as climate changes more rapidly

than they can evolve, it poses a threat to

their existence.

Past rapid climate change

• Associated with three mass extinctions in

fossil record

– Dinosaurs

• Cretaceous 65 mya

• Triassic 200 mya

• Permian 250 mya

Common effects of present

increasing temperature

• Expanded or shifted geographic ranges

– mammal, bird and insect species extending

toward the poles and up mountains

• grizzlies, pika

• earlier spring events for birds, insects &

plants

– migrations, hatchings and seed germination

• disconnection of ecological relationships

– winter moth caterpillars & English oak

Rising winter & night-time

temperatures

• Increased survival of forest insect pests and

tree pathogens

/

www.fs.fed.us/.../whitebark_pine/assessment.htm

Mountain pine beetle damage in

Rocky Mountains

hflp.sdstate.edu/Pestalrt/alert805.htm

concerns?

Eastern hemlock wooly adelgid

http://na.fs.fed.us/fhp/hwa/

www.flickr.com/photos/greendestiny/177374293/

www.uri.edu/ce/factsheets/images/hemlockadelgidRAC.jpg http://cdn2-b.examiner.com/

Changing precipitation patterns

• Costa Rica's

Monteverde Cloud

Forest Preserve

Golden toad

(footage)

http://news.bbc.co.uk/1/hi/sci/tech/328776.stm

Presumed extinct

4. Overexploitation

Concept:

If individuals of a species are harvested more

quickly than they reproduce and grow, then

their populations will be suppressed or even

eliminated.

Most conspicuous examples –

terrestrial vertebrates

Birds: dodo, passenger pigeon

Mammals: primates, big cats, wolves,

bears, rhinos, elephants

Why?

Marine examples

Mammals – whales

Fish - cod, tuna, swordfish, shark

Northern bluefin tuna

http://www.worldwildlife.org/photos/northern-bluefin-tuna--2

onemoregeneration.orghttp://www.cbs.com/shows/cbs_this_morning/video/bA3DOReFqaMRG

mq4JZgXOpgX2BvWTtM2/-world-s-best-sushi-chef-gives-dire-warning/

Bycatch

– reptiles (sea turtles)

– fish (sawfish)

– mammals (dolphins)– https://www.youtube.com/watch?

v=PyGHk6zIL-Y

5. Pollution

Concept:

When habitat for a species is contaminated,

the species may suffer reduced reproduction

and growth, threatening its survival.

Pollutant types

• Excess nutrients – eutrophication

– Sequence leads to oxygen depletion in waters

– Ultimately dead zones & fish kills

www.sudburyvalleytrustees.org-

www.ecology.com-

Pollutant types

• Industrial chemicals & pesticides

– DDT

• previously threatened American bald eagle

– and related chemicals – endocrine disruptors

• Florida panther

www.zmescience.com

Distilling down the threats to

biodiversity

“The cost of doing business”

• Massive cost externalization

• Does not have to be like that … options?

– Sustainable development