ecological monitoring Flashcards
what is population growth?
-populations grow, shrinks or remain stable due to births, deaths, immigration and emigration
-populations growth rate= (birth rate + immigration) - ( death rate + emigration)
what is carrying capacity?
-greatest population that an area can support indefinitely without damaging or over-exploiting the environment
-the mortality rate changes if the population is above or below the CC, to restore the balance
what is artificial population control?
-when natural control mechanisms are no longer present
-e.g. culling overgrazing red deer in scotland as wolves have been exterminated
-e.g. introduce non-indigenous species ( could be a predator, competitor or pathogen)
-captive breeding and release programs, removal of predators
what is r-selection?
-early age of maturity
-large number of young
-semelparity
-no parental care
-a large reproduction effort
-e.g. mice, rabbits, locusts, greenfly
what is k-selection?
-delayed reproduction
-small number of young
-iteroparity
-parental care
-smaller reproductive effort
-e.g. whales, elephants, rhinos
what are advantages / disadvantages of r and k selection?
- r-selected species can respond rapidly to sudden death rate increase
- r-selected species can disperse widely, energetically cost
- k-selected species may experience a sudden population crash- may be impossible to recover from
-long lived- may be resilient to short term conditions
what are pros of satellite tracking?
-not intrusive
-improvements in tech
-generated lots of data
-essential approach for many species
-identify features for feeding, resting, breeding
what are the cons of satellite tracking?
-attaching collars
-data retrieval
-battery life
-cost
-weight
-prone to failure
what is historical tracking?
-fit animals with transmitters
-track radio signals with receivers on the ground
what are current receivers?
-receivers high above ground
-orbiting space satellite can hear a transmitter
-even if the animal is out of sight over the horizon, the satellite can hear the transmitter and respect its signal to trackers on the ground
how are animals tracked?
-radio transmitter strapped to an animal
-signal sent from the transmitter up to a NOAA weather satellite
-this is an uplink
-a signal sent from a satellite to a ground station is a downlink
-at the end of the transmission, the data is sent to wildlife researchers
what do we learn from the data?
-animal/bird activity- motion activated
-longitude/latitude- speed
-battery voltage- slows the battery chemical reaction can reveal temperature
what is photography in specialist monitoring techniques?
-camera traps have minimal impact on the habitat and are one way of ensuring wild animals don’t become accustomed to humans
-can be used to recognise individuals by facial, tail, spots, scars, stripes, fins
-provide info like territory size, population movements, lifespans, social groupings
what are motion sensitive cameras in specialist monitoring techniques?
-activity during the day (visible light) or night (infrared)
-cctv (bird nests)
-put them in trees
what is marking in specialist monitoring techniques?
-rings placed in birds legs provide info on movements and lifespan