benthic invertebrate response to heavy metal contamination in the panther creek drainage (idaho): a...
TRANSCRIPT
Benthic invertebrate response to heavy metal contamination in the
Panther Creek drainage (Idaho): A case study using McQuire’s Metal
Tolerance Index (MTI)
Gary T. Lester – EcoAnalysts, Inc., Moscow, Idaho
Karen Kuzis – Kuzis Consulting, Boise, Idaho
Purposes:
- Give a brief description of the metal tolerance index (MTI)
- Give an overview of the Blackbird mine and associated water quality issues
- Discuss the MTI response to copper during a baseline study conducted last fall.
OVERVIEW OF THE MTI
McGuire’s Metal Tolerance Index (MTI) was developed using benthic invertebrate communities and associated metal data (copper) in Montana’s Clark Fork River
Calculated as a weighted average of tolerance values assigned to each species (similar to HBI)
Score ranges from zero (highly intolerant) to ten (highly tolerant)
0-3 = no impact; 7-10 = significant impact; 3-7 = ???
OVERVIEW OF THE MTI (CONTINUED)
- The index has not been published in a peer-reviewed journal
- The index has been criticized for lack of peer review
Blackbird MineBlackbird Mine
Located 20 miles SW of Salmon, ID in the Salmon NF
Currently inactive
Mined from 1900 – 1982; most active from 1949 – 1967
Mining operations have created 10 miles of tunnels, 4.8 million tons of waste rock, 2 million tons of tailings, numerous adits and portals
Tailings originally dumped directly into Blackbird Creek until 1950’s, after which tailings were dumped into an impoundment
Blackbird Mine (continued)Blackbird Mine (continued)
In 1982 a water treatment facility brought online to treat discharge from several adits that drain into Panther Creek.
Several sources still contaminating surface waters in the area
Metal Contaminants Present in Surface Metal Contaminants Present in Surface Waters:Waters:
ARSENIC
COBALT
COPPER
MANGANESE
ZINC
NICKEL
NATURAL RESOURCE USES:NATURAL RESOURCE USES:
Panther Creek historically served as spawning and rearing for Chinook and Steelhead
Anadromous runs dropped sharply following development of the mine
In 1954 fish kills of salmon, steelhead, trout and whitefish occurred – believed related to acid releases from the mine
Currently, aquatic biota are either non-existent or severely damaged in Meadow, Bucktail, SF Big Deer and Big Deer Creeks
THE STUDYTHE STUDY
A proposed expansion for a cobalt mine requires a pre-operation baseline inventory.
On August 17-18, 2001 benthic macroinvertebrates were collected from the following locations:
Sampling Stations:Sampling Stations:South Fork Big Deer Creek
SF-3 Above Bucktail Cr. SF-2 Below Bucktail Cr.
Sampling Stations:Sampling Stations:Big Deer Creek
BD-5 Above SF Deer Cr. BD-4 Below SF Deer Cr.
Sampling Stations:Sampling Stations:
Panther Creek (no photos available)
FIELD METHODSFIELD METHODS
Benthic invertebrates collected using modified Hess, 500 micron mesh, 0.10 meters sq.
3-Hess composite (across a transect) in riffle habitat
3 riffles sampled per site (3 reps/site)
Total of 0.9 meters sq. sampled at each site
LAB METHODSLAB METHODS
Fixed count/known area subsampling approach (500 count) using a modified Caton subsampler
Invertebrates identified to genus/species where possible including Chironomidae and Oligochaeta
RESULTS
Water Quality – Dissolved CopperWater Quality – Dissolved Copper
0.0004
0.0789
0.0017
0.0202
0.0025
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
SF-3 SF-2 BD-5 BD-4 P1 P2
Mea
n D
isso
lved
Cu
(m
g/l
, n
=5)
TOTAL DENSITYTOTAL DENSITY
0
2000
4000
6000
8000
10000
12000
14000
SF-3 SF-2 BD-5 BD-4 P-1 P-2
Den
sity
(#/
squ
are
met
er)
TAXA RICHNESS AND EPT TAXA RICHNESS AND EPT RICHNESSRICHNESS
43
12
60
32
5444
21
4
27
12 17 12
0
20
40
60
80
SF-3 SF-2 BD-5 BD-4 P-1 P-2
Tax. Rich. EPT Rich.
% Dominance (3 taxa% Dominance (3 taxa))
0
20
40
60
80
SF-3 SF-2 BD-5 BD-4 P-1 P-2
THE DOMINANT CRITTERSTHE DOMINANT CRITTERS
Micropsectra sp. Baetis bicaudatus Pagastia sp.
Diamesa sp. Pagastia sp. Baetis bicaudatus
SF-3 SF-2
THE DOMINANT CRITTERSTHE DOMINANT CRITTERS
Heterlimnius sp. Cinygmula sp. Stempellinella sp.
Pagastia sp. Orthocladius
(Orthocladius) sp. Orthocladius
(Euorthocladius) sp.
BD-5 BD-4
THE DOMINANT CRITTERSTHE DOMINANT CRITTERS
Baetis tricaudatus Cladotanytarsus sp. Optioservus sp.
Baetis tricaudatus Optioservus sp. Cladotanytarsus sp.
P-1 P-2
Taxa eliminated or reduced:Taxa eliminated or reduced:
SENSITIVE MAYFLIES
CHIRONOMIDAE IN THE TRIBE TANYTARSINI
MTIMTI
0
1
2
3
4
5
6
7
8
9
10
SF-3 SF-2 BD-5 BD-4 P-1 P-2
MTI vs. Dissolved Copper*MTI vs. Dissolved Copper*
0
1
2
3
4
5
6
7
8
9
10
SF-3 SF-2 BD-5 BD-4 P-1 P-2
0.0004
0.0789
0.0017
0.0202
0.0025
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
SF-3 SF-2 BD-5 BD-4 P2 P1
Mea
n Di
ssol
ved
Cu (m
g/l,
n=5)
R-squared = 0.809, n=5
*No copper data at P2
MTI Dissolved Cu
MTI vs. HBIMTI vs. HBI
4.493.84
4.45
3.364.2 3.86
0
1
2
3
4
5
6
7
8
9
10
SF-3 SF-2 BD-5 BD-4 P-1 P-2
MTI
HBI
R-squared = -0.597, n=6
TOLERANCES TOLERANCES CANCAN DIFFER SIGNIFICANTLY FOR DIFFER SIGNIFICANTLY FOR ORGANIC VS. METAL CONTAMINANTS!!!ORGANIC VS. METAL CONTAMINANTS!!!
HBI MTICinygmula sp. 0 0
Baetis bicaudatus 2 4
Heterlimnius sp. 3 3
Pagastia sp. 1 9
Diamesa sp. 5 9
Orthocladius sp. 6 5
Micropsectra sp. 4 1
Rheotanytarsus sp. 6 1
Stempellina sp. 2 0
Stempellinella sp. 4 1 (suggest)
Tanytarsus sp. 6 3
Parting Shots:Parting Shots: In this case study the MTI was useful in tracing the
impact of metals as contaminated water flowed from headwaters to Panther Creek
The MTI shows promise as a diagnostic tool for stressor identification (metal contamination), although a more rigorous evaluation is suggested
In addition to EPT, Chironomidae are useful bioindicators of metal impacts when identified at least to genus level.
The MTI was negatively correlated with HBI
Parting Shots (continued):Parting Shots (continued): The next generation of bioassessment tools is focusing
on impact source determination (stressor identification)In order to develop these tools, we can help by having our invertebrate samples accurately identified to lowest practical level
In addition, good physical and chemical data collected with invertebrate samples over a range of conditions will be extremely helpful
Over time, enough real-world data will be collected to develop the associations necessary to assign accurate tolerance values to each taxon (e.g. Brandt, Relyea)