amphibian conservation exam 1

batrachology

batrachology

study of amphibians

why are amphibians and reptiles studied in groups

• historical inertia

• tradition

• aspects of their lives/biology are similar

• studied using similar techniques

• ideal models in experimental ecology

differencens in amphibians and reptiles

• skin

• skeleton

• reproduction

• amphs 3 chambered heart

• pokilothermic

heterochrony

alterations in the timing/rate of developmental processes (during embryo stage) hat change he body form of adults

factors that affect physiological processes of juveniles and adults

• temperature

• water availability

• gas exchange

metamorphosis

• signals completion of embryogenesis

• initiated internally by hormone thyroxine

what can initiate early release of thyroxine

environmental factors

intermediate (attenuated) growth

allows more growth and stores more energy

determinate (asymptotic growth)

allows earlier reproduction and more often

factors that affect ultimate size of individual

• genetic potential

• size at hatching

• abundance/qualitty of food at juvenile growth

• organisms sex

how many cranial nerves do amphibians have

10

cutaneous sense organs

• mechanoreceptors

• lateral line

• tactile

respiratory surfaces

• skin

• gills

• lungs

• buccopharyngeal

amphibian life cycle

• tied to water for reproduction

• mostly intternal fertilization

• indirect and direct development

• bipahsic and biennial

salamanders found worldwide excluding

• australia

• antartica

• most of Africa

highest concentration of salamanders found in

Appalachian mountains

1/3 of salamanders found in

North America

types of amphibian diversity

• form

• size

types of variation in amphibians

• geography

• age

habitat affinities for amphibians

• forest

• savannah

• grassland

• shrubland

• secondary terrestrial habitats

• flowing freshwater

• marsh/swamp

• still open freshwater

• arid habitats

global distribution of threatened amphibians

• North/south America

• china

• australia

• africa

6 reasons for amphibian decline

1. habitat alteration

2. invasive species

3. pollution

4. unsustainable use

5. disease and parasitism

6. climate change

hotspot to qualify as a region

• contain more than half of the worlds vascular plants as endemics

• lost at least 70% of its original habitat

what drives diversity and abundance of salamanders in the southern Appalachians

diverse ecogeography ( ridge and valley to coastal plain)

family that makes up 90% of salamanders and contributes to diversity in southeast us

plethodontids

why are amphibians mostly bioindicator species

• permeable skin

• found in and around water

• reproduction tied to water

• complex life cycle

• physiology makes them more sensitive to water quality

current issues

• political ecology

• trade in exotic wildlife

• sport or commercial hunting/fishing

habitat modification, fragmentation, loss

• habitat degradation

• urban sprawl and fragmentation

• wetland mitigation banking (wolf in sheep’s clothing)

disease and proposed impacts

• GTFP

• URTD

• amphibian abnormalities

• Bd and rana virus

• amphibian die offs

pollution and suspected affects

• heavy metals and allies (lead, mercury)

• PCBs, PFOs

• environmental acidification

• estrogens

categories of pollution

• solid waste

• nutrient oversupply

• pesticides/herbicides

• sediments

• particulates/ acid forming compounds

• photo-chemical smog/ CO2

• CFCs

• toxic chemicals

pests

anything that is not wanted, likes, or deemed useful

need for pest control

• mostly driven by anthropocentrism and utilitarianism

• agriculture

• human health

promises of pesticides

quick, dirty economical fix

problems of pesticides

• resistance build by pests

• resurgences and secondary pest outbreaks

• environmental and human health problems

alternative pest control methods

• cultural control

• biological control

biological control examples

• natural enemies

• genetic control

• chemical ecology

• physical and natural product or barriers

• control with sterile masks

• biotechnology

integrated pest management IPM

control pest populations by using chemical and ecological methods in a way that brings long term management of pests with minimal environmental impacts

socioeconomic issues in pest management

• cost benefit analysis

• economic threshold

• insurance spraying

• cosmetic spraying

exotic species

non-native species that have been introduced to an area

chameleons in hawaii

marine toad in australia

introduced predators and human commensals

• cats

• rabbits

• goats

• skunks

• etc

exotic or invasive plants

• water hyacinth

• multiflora rose

• reed canary grass

factors contributing to harvest

• pet trade

• commercial fishing

• bush meat/ skin trade

• cultura/ medicinal

• sport

max sustained yield

point where population declines if this value is exceeded

optimum sustained yield

level of sustained yield determined by

• species interactions

• esthetics

• land use problems

problems with sustained yield management

• fixed quota

• dynamic pool model

fixed quota

% is removed from the population each year (harvest) based on MSY estimates

dynamic pool model assumptions

• constant natural mortality rate is independent of density & same for all age classes

• growth rates age specific/unrelated to density

• animals removed replace the lost via density related natural mortality

conservation through commercialization causes

• mixed messaging

• green washing: making things seem env when they aren’t

ethics and the ark

zoos give false sense of security for animals, its not the ark

reservation and management

• reserves and corridors

• captive management

• augmentation, repatriation, introduction

problem with reserves and captive management

halfway technologies that do little towards solving the root of the problem

order of extinction

1. individuals

2. populations

3. species

population explosion usually leads to

• overexploitation

• collapse of ecosystem

reasons for explosion

• rich/poor nations

• population growth in rich/poor nations

• different populations present different problems

positive effects of increasing affluence

• many forms of pollution decrease

• ability put more money into management and conservation efforts

negative effects of increasing affluence

• high use of fossil fuels

• produce large amounts of co2

• CFCs and PCBs

urban sprawl

urban/suburban network of low density

• residential areas

• shopping malls

• industrial parks

laced together by multilane highways

origins of urban sprawl

• automobiles

• post WW-II

environmental impacts of urban sprawl

• depletion of energy resources

• air and water pollution

• loss of agricultural land

• loss of natural landscapes/ wildlife

reigning in urban sprawl

• setting boundaries

• saving open spaces

• developing existing urban space

• revitalizing towns by integrating multituse platforms

urban blight

• general deterioration of structures and facilities

• decline in quality of services (education in inner cities)

lifeboat ethic

argument to the effect that food aid should be limited to high population countries too prevent population growth

PARC mission

conserve amphs/reps and their habitats as integral parts of ecosystem/culture through proactive/coordinated public/private partnerships

PARC priorities

• educate about herpetofauna/conservatiton

• establish habitat/ecology database

• standardize techniques

• create management database

• establish PARC fellowship program

inductive hypothesis

investigator gathers empirical data and arrives at a generalization from it

deductive hypothesis

• investigator develops general idea about phenomenon and performs experiment

• makes specific predictions from experiments that can be tested again

scientific inquiry

1. perceive that problem exists

2. make hypothesis

3. make alternative hypothesis

4. identify best approach to test hypothesis

5. collect/analyze data

6. support/reject hypothesis

7. understand implications of results

8. modify hypothesis, repeat experiments

levels of study

• descriptive natural history

• natural experiment

• laboratory experiment

• integrated research process

3 working hypothesis

• statistical (null)

• research (theory)

• alternative

experimental approach

• directly determines the response of dependent variable to variation in independent variable

• investigators control independent variable

• control group

• replicates to account for uncontrolled variation

long term ecological research

to better understand key ecological processes (recruitment, survivorship, competition)

• life history and demography

short term ecological research

more limited in scope and what you can extract from the data butt not negative or lesser

• habitat selection, seasonal cycles

required for successful study

• temporal and spatial scale

• inappropriate scale limits inference of results

• scale and research objectives highly interconnected

choosing model organism

• understand its life history

• role of keystone species, umbrella species and flagship species

choosing study site

• location

• access

• target species

• knowledge of study area

• consequence of convenience sampling

pilot study

• preliminary run through of all phases of project

• provide insight on

  • cost

  • method problems

  • variance estimates

variance

measure of error

models

abstract representation of real system

types of models

• statistical

• non-statistical

• analytical

• simulation

• conceptual

SMART approach

1. specific

2. measurable

3. attainable

4. relevance

5. time

field experiments involve

manipulation of one or more independent variables

descriptive research

• important

• natural history studies

• initial or essential phase

• pilot study

• broad objectives

• lack of exp control

experimental research

• most powerful

• theoretical/applied studies

• specific tests, hypothesis

• positive and negative controls

why are trendy methods questionable

• may our may not last long

• less information found on trendy methods

sampling

• replication

• sample size

• statistical power

• controls

simple random sampling

randomly generating point at time for one variable to be measured

stratified random sampling

blocks or layers of sampling at random

pseudorandom sampling

• random spots measured multiple times

  not ideal sampling, violates concept of replication

systematic smapling

• same way each and every time

• looking at trends through time

• must be consistent

cluster sampling

• sampling based on biological attraction points

• focuses on naturally occurring things in landscape

biological attraction points

• areas in the landscape that have been identified

• something about the biology of that point attracts something to it (water in frog study)

road sampling

• picking points at set distance from road

• convenient

• can underestimate what’s out in the wild

point sampling

• software built random points for an area

• sample what’s around the point or directly at it

• increased number of points due to small survey space

point quarter sampling

• based of points in area

• points pulled randomly, stratified or systematically

• quarter points into 4 sections to survey

line transect sampling

forms parallel lines through area

plots along transects sampling

• provides path for points on transects

• build plots of points

hap hazard sampling

• wrong

• wander around

• could be used for preliminary to decide what sampling method to use

data collection

• recorded on preprinted data sheets

• duplicated after field day and stored in separate location from original

• proofread for accuracy

common problems of sampling

• sample size

• procedural inconsistency

• non-uniform treatments

• pseudoreplication

• improper design or statistical tests