survey design for monitoring north american native bees
DESCRIPTION
This slide show was presented at the 2009 North American Pollinator Protection Campaign meetings in Washington D.C. It was designed to brief the participants about plans to develop a statistically relevant but inexpensive means of determining if our bees are declining. Details can be obtained from Sam Droege ([email protected]).TRANSCRIPT
the problem.
the world suspects bees are declining
Shrill Carder Bumblebee DistributionData from NBN, with particular thanks to BWARS.
We do not know if there is a crisis nor have we identified how and where to target our
conservation measures because until now, there is
NO NORTH AMERICAN MONITORING PROGRAM
the solution.
develop a monitoring plan
Evaluate methods
Determine where and how many sites you would need to detect declines
Evaluate cost
methods
CV = SD/Mean
It doesn’t matter which technique you use, so go with cheap, easy and standardizable.
0 5 10 15 20 25 30 350
5
10
15
20
Minckley Dry Site 8
Mao TauChao2Jack2
Number of bowls
Num
ber o
f spe
cies
24 pan traps per transect 8 blue8 yellow8 white
Sample every 2 weeksAt a minimum, sample every fifth year on a rolling basis
methods
develop a monitoring plan
Evaluate methods
Determine how many sites you would need to detect declines
Evaluate cost
decisions
used multi-year trap studies
estimated number of samples using power analysis
good versus bad sampling
>80% probability of detecting a change if one is occurring
> 1-3% change in population per year
declines
Years
2 4 6 8 10
Pe
rce
nt
Re
ma
inin
g
0
20
40
60
80
100
1% Annual Decline2% Annual Decline5% Annual Decline7% Annual Decline
How many sites?Detecting a decline in the number of species
= 0.20
Number of Sites Monitored
50 100 150 200 250 300
Po
we
r
0.0
0.2
0.4
0.6
0.8
1.0
1% Annual Decline2% Annual Decline5% Annual Decline7% Annual Decline
= 0.20
Number of Sites Monitored
50 100 150 200 250 300
Po
we
r
0.0
0.2
0.4
0.6
0.8
1.0
1% Annual Decline2% Annual Decline5% Annual Decline7% Annual Decline
How many sites?Detecting a decline in the abundance of bees
number of sites
with 100 sites, we should be able to detect even a 2% decline in both the abundance and number of species
of bees
with slightly over 200 sites, we can pick up a 1% decline
many individual species can be monitored
Wow
develop a monitoring plan
Evaluate methods
Determine where and how many sites you would need to detect declines
Evaluate cost
product
• Results in 5 years– Change in abundance– Change in total species– Changes in major guilds and genera– Changes in common abundant species– Maps of distributions– Maps of change– Public database of all records– Tons of specimens for collections, dna, revisions, display,
etc.– Web-based yearly reports
longer term results
long-term product
• Trends for individual species• Regional trends• Ability to detect large scale crashes for any
year• Ability to compare to Canadian system• Ability to compare to European system• Ability to compare to UN-FAO sites
more long-term product
• Standardized methodology permits comparisons among sites– Patterns of distribution– Patterns of abundance– Patterns of composition– Patterns of fluctuations– Community analyses– Biogeography analyses
the cost.
cost per site
Labor
Collection • a few hours
Processing• 1/10 of an FTE
• each site run only every 5 years
Supplies and Equipment
• $2,200
other costs
Full time coordinator for the length of the project
develop a monitoring plan
Evaluate methods
Determine where and how many sites you would need to detect declines
Evaluate cost
a future.
4 separate sampling systems – National Forests– Fish and Wildlife Service Refuges– National Parks– Commercial Orchards or other Ag Systems
usfs
sampling – For each of the four groups
year 1 – 50 new sitesyear 2 – 50 new sitesyear 4 – 50 new sitesyear 5 – first 50 are repeated…und so weiter
centralized processing
• 2 sorting, processing, identification, and databasing centers (West and East)
• 170,000 bees a year between the two• Efficiency of scale• 1 central coordinator• 2 FTE’s doing the specimen processing
New York Times reports:“Bees in North America NOT declining!” - Laurie Davies Adams,
NAPPC 2015
mission accomplished