329 Biodiversity Final Flashcards
Purple Martin Foundation mission statement
- restore and conserve Western Purple Martin populations along W Coast of NA
- return BC Purple Martins to natural nesting sites in open forest and near freshwater habitats
- eliminate need for human intervention for survival in BC
What do Purple Martins eat
Insects! fly up to high altitudes to catch large flying insects such as dragonflies, moths, beetles, & smaller insects. Dragonflies especially good for hungry nestlings
nootropic migration
A bird that spends the summer in its breeding range in Canada or the United States (the nearctic) but migrates to Mexico, Central America, South America or the Caribbean (the New World or neo-tropics) for its nonbreeding range in winter
Western Purple Martin northern limit of breeding range
north end of Georgia Basin, near Campbell River, VI
PM timing of migration
Adults arrive in BC early-mid April
Younger subadult birds arrive later in May and June
largest BC PM colony
Ladysmith Maritime Society marina in Ladysmith Harbour (67 nests, 2008)
PM colonies
mostly 5-30 nesting pairs in artificial housing and less than 10 pairs where they still occur in the wild in the western USA.
Where do PM’s build colonies
cavities, traditionally woodpecker holes close to water
now, mainly human provided nest boxes- clustered together on marine pilings near/on water
Eastern vs. Western PM nesting
Eastern prefer condo-style or hanging gourds
W prefer individual boxes in loose clusters
How PM’s are being tracked (“new”)
miniature light-level geolocator data loggers recently developed by the British Antarctic Survey (www.birdtracker.co.uk)
how do miniature light-level geolocator data loggers work
record time and light intensity every 10 minutes, allows determination of bird’s position from day length and sunrise/ sunset times
precision of miniature light-level geolocator data loggers
(+/- ~300 km)
battery expectancy >1.5yrs
the PM study
put locators on 20 adults on Central VI, July-Aug 2009
worn until they returned in spring 2010
how are geolocators attached
attached with a tiny “backpack” harness around the legs, a design which neither harms the bird nor interferes with its movements
PM study, year 2
only recovered 1 locator
find migration = ~22,000 km long
applied 10 more locators
PM study, year 3
retrieved 4 locators
added 20 more locators
PM conservation goals
- sustain current highly successful volunteer nest-box-based recovery program
- increase abundance to min 800 nesting pairs by 2012
- re-introduce sig. proportion of population to original/equivalent nesting cavity situations in wild
- redevelop a sustainable wild-nesting population (as far as practical)
BC PM nest box program
1985- installation of nest boxes at Cowichan Bay, probably rescued from extirpation
increased slowly, nest boxes installed at more suitable marine locations
1989- 14 nesting pairs located at 3 nest box sites and 1 piling location on S VI
-2000 ~200 pairs at 16 colonies.
BC PM nest box program, 2000’s
2002- Georgia Basin Ecological Assessment and Restoration Society (GBEARS) takes over and renames “BC Purple Martin Stewardship and Recovery Program”
2005-06, freshwater sites added
PM volunteers
now 145+ volunteers
First Nations, individuals, naturalist/conservation groups, corporations, federal, provincial, regional/municipal government departments, and universities
PM recovery and weather
warm = insects = success– 2006, population tripled
cold wet = less insects = population slows or declines
2008- worst conditions, long cold spring, week of rain at end of July, lack of food = loss of ~100 adults and ~40% of nestlings, subsequent decline in breeding pairs the next year
moving PM’s back to natural sites
Two freshwater sites were occupied in the Fraser Valley area for the first time in almost 40 years – one each in 2006 and 2007. There are currently 1500 nest boxes distributed among 70 marine and 20 freshwater locations.
reasons for bird surveys
simply wanting to know # of species
baseline information for poorly known species/area
land development assessment designation (legal protection)
set priorities to focus conservation efforts
determine habitat associations
why monitor
estimate population trends over time
set conservation priorities
research tool
early pointers for underlying causes of trends
underlying demographic mechanisms
determining success of conservation actions
conservation actions
acquisition of land to protect species
adoption of new management practices
species recovery programs
government environment policies
very important for monitoring
consistency of method is crucial
most common deforestation causes
agriculture, unsustainable forest management, mining, infrastructure projects, increased fire incidence/intensity
indirect effects on deforestation
road building, opening up passages, ‘death by a thousand cuts’
deforestation, Conversion of forests
removing natural forests to meet other land needs, such as pulp/palm/soy plantations, agriculture, pasture for cattle settlements and mining, settlements, roads and infrastructure
deforestation, Forest fires
millions of ha/yr
worse where fires have been suppressed for years (unnatural accumulation makes fire burn more intensely)
deforestation, Illegal and unsustainable logging
occurs in all types of forests across all continents
Illegally harvested wood finds its way into major consumption markets– depresses world timber prices by between 7% and 16%
deforestation, Fuelwood harvesting
Over-harvesting for domestic use or for commercial trade in charcoal significantly damages forests.
deforestation, Mining
often accompanied by major infrastructure construction, such as roads, railway lines and power stations, putting further pressure on forests and freshwater ecosystems
deforestation, climate change
Forest loss is both cause and effect of CC
agriculture, forestry, land-use ~1/4 GHG emissions
leading cause of deforestation
agriculture: oil palm, soy, rubber, coffee, tea, and rice among many other crops – also leads to soil erosion
population index
suitable for determining changes in population size, not exact size - directly related to the unknown population size (ex. if pop. 2X so does index), easier to obtain than pop. size
population size
if you need to know the exact size than a count is needed, not an index, more labour/resource intensive, and never completely accurate either. a good index is preferable over a poor count
true census
attempting to count all birds, pairs, or nests within survey boundary
rare, restricted range bird count
often best to do a true census, sampling might record too few birds for a reliable estimate
high clumped/conspicuous birds
count most of population at limited number of sites
extremely large numbers of birds
within site sampling
common/widespread birds
survey representative section of areas
robust study types
random random stratified regular sampling (systematic)
generic or single species surveys
mapping and transects.
line transect variation
record exact distance from line (variable distance)
record within bands from line (fixed distance)
transect adaptability
marine/freshwater/terrestrial
survey individual species/groups
efficient in quantity/unit effort
transects can be used to
examine bird-habitat relationship
derive relative/absolute abundance measurement
transect issues
recommended walking speed
counting instruction
full distance estimation
full distance estimation
estimating distances from the centre of the point or from the line to all birds heard/seen, or to use estimation w/i bands
-if bands, distances must be predefined
distance estimate, line transect
perpendicular to the transect line (not from observer)
estimating distance
by eye marker posts/coloured tape visually mark position of bird and measure distance when perp. to where bird was plotted on high quality maps use a sighting compass
tools for estimating distance
rangefinder- laser/radar
sighting compass- determine precise angular measurement to bird (then use trig)
using sighting compass
distance from observer to bird
then perpendicular distance is d cos
determining line transects
regular/systematic- series of line oriented along long axis of study area
random- starting point and direction selected randomly
minimum transect recommendations
two visits to a plot each season (max 4)
minimum 2 distance bands (0-25m, >25m)
if multiple observers- assign separate tasks, monitor differences
point transect
stop at predefined spots, allow settle time, record all birds for predetermined time (2-20min)
bluebird populations
1950’s - population declined
1990’s - extirpated
why bluebird loss
loss of cavities (snags)
competition with invasives (starlings, house sparrow)
habitat destruction
how to re-establish blue birds
2012- establish aviaries in garry oak ecosystem for 1-3weeks to acclimate, set them free and hope they establish in nest boxes near the aviary
cost of re-establishing blue birds
$5000/pair
bring back the bluebird goals
reestablish breeding population
replace lost nest cavities
release birds from a healthy population (translocation from washington)
release 90 birds by 2016
bluebird habitat
open parklands
garry oak meadows
open fields
especially: short grass, scattered trees, fence lines to perch on
why North American Red Crossbill excites birders so much
nomadic - don’t see often
red crossbill habitat
cool evergreen forest, Canada-Alaska through Cascades, Sierra Nevada, Rocky Mt’s. wander to find conifer seeds
Red Crossbill characteristics
small, stocky finches
cross tipped bill
hatch w/ uncross bill
crosses at 4-6 wks
why crossbills wander
cone-bearing trees are unreliable - big cone crop one year and the next year nothing
irruption
mass movement of birds, may turn up in unexpected places outside ordinary range
types of red crossbills
up to 9 known, all different bill sizes and shapes and different body sizes depending on kind of conifer seeds they eat - may be evolving in to new species
Crossbill evolutionary arms race
Rocky Mt’s -squirrels take lodgepole cones– trees evolve to produce short, wide cones with thick scales at base
S Idaho- no squirrels– longer, thinner cones, thick scales at tips-
South Hills Idaho Crossbills
bigger bills than other crossbills, more steady populations (more food supply w/o squirrels)
coevolution
changes in at least two species’ genetic compositions reciprocally affect each other’s evolution
most steeply declining species
those associated with mature forests (Pine Siskin, Red Crossbill, Cassin’s Finch, Purple Finch, Pine Grosbeak), vulnerable to loss of mature forest from logging and pine beetle
increasing west coast species
waterfowl (Canada Goose, Hooded Merganser, Ring-necked Duck)
widening and fencing riparian zones
reduce cattle grazing– allows plants to propogate– allows endangered species to persist (Yellow-breasted Chat)
salt
many species of finches are attracted to salts. salt-foraging well documented on highways, coastal mudflats, marsh shores. 1941- at least 1000 killed in one incident.
drone study
204 bird approaches in 8 days with small quadricopter, approached flamingos, greenshanks, mallards
drone study results
80% of cases, could fly to within 4m without modifying behaviour
approach speed, drone colour, repeated approaches no significant impact
approach angle did have significant impact
drone study approach angle
approaching vertically (90º) disturbed behaviour - may be associated w/ predator attack
drone recommendations
lunch >100m from birds
do not approach vertically
adjust approaching distance/species
what is a pitfall trap
hole in ground with cup/bucket in it, typically covered to protect from predation and hypothermia, drainage holes for rain, bedding
drift fence
guard rails, direct animals into pitfalls
what should be recorded when looking at live trap capture
species ID, age, sex, reproductive status, morphometric measurements, capture station number, biological data
what is the purpose of pre-baiting a study site
increases capture (trap-ability); traps baited and left open ≥2weeks
most efficient method of inventorying small mammal population
trapping
types of small mammal trapping
live trapping
pitfall trapping
snap trapping
snap trapping
kill trapping
can provide data for diet or reproduction
very limited as an inventory method
doesn’t capture species/ages equally
disrupts social structure, age structure, behaviour, reproduction, immigration
morphometric measurements
total length, tail length, hind foot length, ear length, weight
marking animals caught in live traps
ear tages
black permanent ink (ventral surface)
hair dye
VI marmot habitat
S & W sub-alpine and alpine meadows (≥ 1000 meters), where trees dont take root– meadows are 1st to become clear of snow, produce early grasses/sedges the marmots rely on after hibernation, deep soils for digging hibernacula, boulders for sunning and scouting
increased marmot breeding success
“dispersal”- leave natal colony to find a mate at a colony nearby or attract a mate dispersing from another colony. both m/f disperse at ~2yrs, ~5-20km
marmot meta population
dispersal creates many mini populations, creates a community of colonies, travelling creates new colonies and helps declining ones, safeguards against total population collapse
when marmots came to VI
not known, but most likely during a glaciation, >9000yrs, glaciation ended, island isolated, evolved in to distinct species
marmot history
1990’s had declined 2/3
1998 70 remained in one small area, well on their way to extinction
2003
marmot mortality
80% from predation -wolves, cougars, eagles
VI Marmot status
Endangered under the federal Species At Risk Act (SARA) and by the Committee on the Status of Endangered Species (COSEWIC). Critically Endangered by the International Union for Conservation of Nature (IUCN)
logging and Marmota
habitat changes affect predator/prey relationships
clade
group of organisms that consists of a common ancestor and all its lineal descendants, and represents a single “branch” on the “tree of life”.
vicariance
process by which the geographical range of an individual taxon, or a whole biota, is split into discontinuous parts by the formation of a physical or biotic barrier to gene flow or dispersal.
allopatric speciation
occurs when biological populations of the same species become vicariant, or isolated from each other to an extent that prevents or interferes with genetic interchange
allopatric speciation of Sorex (water shrews)
best guess- separated by the mountain range. possibly at last glacial extent, land was essentially higher and they could mix/disperse easier, now are isolated
molecular biology- identifying species
removes personal opinion, doesn’t rely on sometimes unclear physical features
