lecture 6 - dingoes Flashcards
wht are some important cultural aspects to consider?
> based on casual observations - over generations - over millennia > wide spread in time and space > not necessarily testing hypotheses > not always statistically amenable
what are some aspects of scientific knowledge?
> based on intensive directed studies
confined to a specific context in space and time
. not always generally applicable to other places and times
hypotheses often reductionist sometimes ignoring important factors
what is the taxonomic status of dingoes?
> have had lots of names since european settlement
1980’s Canis familiaris dingo
- because the dog was C. familiaris and the dingo was a sub-species
lately, Canis lupus dingo
- because recent DNA testing indicates dingoes descend from C.lupus (wolf) - so does the dog
there is still debate e.g., Crowther et al. 2014 argue for Canis dingo
dingoes do interbreed with feral C.lupus familiaris (dog)
are dingoes native or feral?
> firstly, fleming et al 2012 argue that all wild dogs in australi are non-native n the strictest sence
- they are domesticated versions of wolves descending from canids that became feral
carthey and banks 2012 argue that they should be considered and treated as natives
- in australia for 4000 years
- prey species respond to them as predators more than they do to more recent arrivals
- they have assumed important functional roles in ecosystems as top predators
do dingoes harm conservation or aid it?
> aid it
they are top predators that suppress ‘mesopredators’
mesopredator release hypothesis
- dingoes suppress cats and foxes
- cats and foxes are major threats to CWR mammals
cessation of dingo control benefits threatened mammal and other populations
density of foxes always low in presence of high densities of dingoes
dingoes make cats shift their activity patterns and hunt in suboptimal conditions
dingoes also kill and eat cats
do dingoes have any benefits to vegetation?
> yes
dingoes regulate kangaroo populations
dampening the boom and bust cycles seen in outback australia
avoiding overgrazing of grass when roo numbers are particularly high
mitigating effects of erosion and soil loss following ground cover loss
what is the legislated conservation status of dingoes?
> protected in the NT
may be controlled in te ACT with authorisation
controlled south of the fence in SA, somewhat protected to the north
prohibited in tasmanina
controlled as pest species in Vic, NSW and WA, except in parks where they are protected
what is the dingoe protection status of queensland?
> protected in national parks and other protected areas
still widespread
the dingo is not endangered
may be in danger of becoming hybridised with feral dogs
what is the health status of dingoes on fraser island?
> a perception they rely on human provided human food
- deliberate feeding is now band
- inadvertent feeding from camp sites ( open unattended food boxes etc)
- discarded food
- fish scraps left by anglers
- picnic areas and rubbish dumps (now fenced off)
most are lean, rather than thin
slightly heavier than mainland dingoes
leaner than many domestic dogs which are often overweight.
what do dingoes eat
> wallabies and kangaroos where available
wombats as well, coastal NSW ( and elsewhere)
townshend island (no wallabies, kangaroos or other large native mammals) goats, then sugar gliders
shoal water bay ( no goats either): possums, bandicoots and gliders
during drought when macropods are less common: carrion, often cattle
in western deserts, smaller mammals such as rabbits, in particular, and CWR natives
even lizards such as goannas according to availability
in dense, wet, tropical forest, small (CWR) mammals
flexible in diet
describe the hunting behaviour of dingoes
> if large mammals available, hunt in groups
sub packs, 2 or 3, within larger packs 2 to 12 in NW Aust
ca deal with animals larger than themselves and share the high return from a single successful hunt
if only small prey available, then hunt alons
what else efects pack size?
> habitat or local vegetation structure might also have an effect on pack size
closed forest might preclude effective pack hunting
so perhaps they hunt only small prey in rain forests, even if pademelons or wallabies are available
what has flexability promoted
> flexible diets and behaviour have allowed dingoes into many habitats: they have a wider fundamental niche
together, as a terrestrial mammal, Canis lupus is more widespread globally than any other except Homo sapiens
as well as that, they can take advantged of H.sapiens
how do we investigate dingo diet?
> survey techniques are many and various
include live trapping and camera trapping
hair trapping
hair can be identified under microscope, often to species of mammal
if dingoes ate food randomly, then the proportion of a given species in their diet should equal the proportion of that species in a random sample of those available
if they prefer a particular species then the proportion of that species in the diet would be higher
what is the electivity index?
> Ei = (ri-ni)/ (ri+ni)
ri = proportion (or % age) of species i in diet
ni = proportion (or %age) of species i in environment
