NORTH RIVER FISH KILL PRELIMINARY REPORT 2014 SUMMARY

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1 NORTH RIVER FISH KILL PRELIMINARY REPORT 2014 SUMMARY A fish kill on Nor River was reported to e Environmental emergency number on August 9, Representatives from e PEI Department of Environment, Labour and Justice, PEI Department of Agriculture and Forestry, and Environment Canada responded to e incident. The 1,155 fish recovered represent a small portion of e estimated 4,560-10,973 salmonids killed. Heavy rainfall was recorded on August 6-7, Fish necropsy results from e Atlantic Veterinary College showed no evidence of disease. The presence of moderate to large amounts of food in eir stomachs is indicative of a sudden, acute dea. The Department of Environment, Labour and Justice and Environment Canada are investigating. A final report will be issued when e investigation is complete. BACKGROUND At 8:43 AM on August 9, 2014, a caller to e Environmental Emergency line reported seeing a number of dead fish at e Old Route 2 road in Springvale. The Department of Environment, Labour and Justice (DELJ) Environmental Emergency Response Team member notified a conservation officer who arrived at e Old Route 2 Road at 9:27 AM. DELJ s emergency response member and Conservation Officers, e Department of Agriculture and Forestry s (DAF) freshwater fisheries biologist and an enforcement officer from Environment Canada also responded. INSPECTION DETAILS First responders initially observed dead brook trout below e Route 2 crossing and began collecting water quality information (water temperature, dissolved oxygen, salinity and conductivity) at is crossing at 9:40 AM. The condition of e fish indicated at ey had Figure 1. Location of e Nor River fish kill The portion of stream affected is outlined in red..

2 been dead for some time. DELJ responders walked upstream from e Old Route 2 crossing and continued collecting water quality information at various locations. The Freshwater Fisheries Biologist and Senior Conservation Officer joined e first responders as ey worked to identify e uppermost affected area and potential source of e fish kill. Dead fish and dead slugs were observed roughout e stream from e Crabbe Road to e headwater regions of e Ebenezer branch in Nor Milton. The stream bed was covered in a film of fine sediment. Near e headwaters, fresh mounds of sediment were observed in e stream channel and gullies were observed on e east side of e stream. The Ebenezer tributary forks in e headwaters, wi e nor branch becoming intermittent and reduced to a dry stream bed near residences along e New Glasgow Road (Rte 224) in Ebenezer. The oer fork is a small stream originating on e east side of Route 224 in Nor Milton. During e August 9 investigation, live fish were seen on e nor branch immediately upstream from e junction of e two branches. No additional dead fish were observed upstream from is location. Buffer zone measurements, and water, soil and vegetation samples were collected. All samples were transported to e Environment Canada Laboratory in Moncton. Fish samples were collected at various locations wiin e affected area. Some of e fish were wrapped in tinfoil and transported to Moncton. Oer fish were collected and kept frozen in lockup at Beech Grove until submitted to e Atlantic Veterinary College on August 11. ENVIRONMENTAL CONDITIONS - RAINFALL Environment Canada recorded rainfall amounts in Charlottetown of 38.6 mm between Wednesday August 6 and Thursday August 7. The University of Prince Edward Island s Climate Research Lab monitoring station in Winsloe Sou recorded 24.1 mm of precipitation on August 6, wi 23.1 mm of rain falling between 5:10 PM and 5:50 PM. Total rainfall on August 7 was 20.8 mm. Hail was also recorded in Winsloe on August 6. Precipitation during is period was localized so e amount of rainfall received at e site of e fish kill may have varied. FISH CLEAN UP Clean-up of dead fish began on August 10, wi e freshwater fisheries biologist and wildlife technician from e Department of Agriculture and Forestry joined by four members of e Central Queens Wildlife Federation s summer crew. Three people began at e Milton Bridge on e Nor Yorke River Road (Route 248) and ree oers started at e Route 2 crossing in Springvale. Water levels were high from Milton Bridge to e forks of e Loyalist Road/Springvale branches as a result of Super Moon tides. Four dead fish were picked up below e forks and dead fish were observed roughout e stream to Route 2. The upstream crew completed a short distance upstream from e Crabbe Road on August 10. Difficult walking conditions rough alders and debris, and e high numbers of dead fish in is section, made e cleanup difficult. On August 11, e Cornwall and Area Watershed Group and

3 Wheatley River Improvement Group completed e cleanup of dead fish to e headwaters near Ebenezer. A total of 1155 fish were collected on e 3.8 kilometres of stream affected. The greatest number of fish retrieved (934) was in e section upstream from Route 2 in Springvale. The mortality included 825 brook trout, 78 rainbow trout, 26 Atlantic salmon and 226 ree-spined sticklebacks. Measurements of individual fish were not taken due to e decomposed nature of e fish. However, all fish were less an 25 cm (10"). During e clean up, it was observed at e bottom was covered in a layer of fine sediment. There was an abundance of live caddisfly larvae on e streambed and on some fish carcasses. Many dead slugs were observed on e bottom of pools roughout e affected section. Very few live fish were observed. RESULTS ATLANTIC VETERINARY COLLEGE - FISH NECROPSY Eight brook trout and one stickleback were submitted to e Atlantic Veterinary College. Only e largest fish could be examined in detail as e oers were quite decomposed. There was no evidence of disease in e fish. The examiner noted at six of e eight trout examined had moderate to a large amount of food in eir stomachs which would be indicative of a sudden acute dea. PEI DEPARTMENT OF AGRICULTURE AND FORESTRY - SOIL AND WATER ENGINEER ASSESSMENT As recommended by e Report of e Action Committee on Sustainable Land Management, soil and water engineers arrived on site on August 11, Their observations have been provided to e Department of Environment, Labour and Justice.

4 Figure 2.Location of electrofishing locations on Nor River, August FISH POPULATION IMPACT ASSESSMENT st On August 20 and 21, electrofishing surveys were carried out to assess densities of salmonids in affected portions of e Nor River. Two sites were assessed using standard ree pass removal techniques - one site immediately downstream from Route 2 in Springvale and e oer between e Crabbe Road and e headwaters in Nor Milton. Density of brook trout and rainbow trout at e Springvale site on August 20, 2014 was 26 fish/100m2. In comparison, only one brook trout was captured at e upstream site in ree complete passes wi e electrofisher, us e density could not be calculated (less an 1 fish/100m2). No Atlantic salmon were captured at eier location.

5 2 Salmonid densities are calculated as e number of fish per habitat unit (100m ). This allows comparison of various rivers and between sites on a particular watercourse. There are approximately 131 habitat units in e 3.8 km of affected stream on Nor River. Estimates calculated using pre-kill estimates of fish/hu confirm at many more salmonids were killed ( ) an what were retrieved during e cleanup. The estimates were made using densities in e lower range of what would be expected for is type of habitat and assuming 50% mortality in lower reaches and 95% mortality in headwater sections. The low density of fish at e Springvale site in our electrofishing surveys and e lack of fish in e upper site are indicative of extensive mortality. Wi e upper affected area so close to e headwaters, ere is little habitat upstream to provide fish for restocking. Stocking of fish into e affected area would accelerate repopulation efforts. Note: No estimate is provided for e number of sticklebacks affected by e fish kill. The fish in Nor River had been dead for approximately ree days before e clean up began. The longer e delay in picking up dead fish, e greater e likelihood at many of e carcasses have been buried in sediment or picked up by scavengers. Labay and Buzan (1999) documented at after 16 hours, only 39% of e fish deposited in a stream were accounted for. The 929 salmonids retrieved in Nor River represent a small portion of e total actually killed. The mortality estimates suggest at 9% to 20% of salmonids killed were retrieved during e cleanup. REFERENCES Labay, A.. And D. Buzan A comparison of fish kill counting procedures on a small, narrow stream. Nor American Journal of Fisheries Management. 19:

6 Figure 3. Nor River brook trout covered in caddisfly larvae. August 9, Figure 4. The Central Queens Wildlife Federation crew picks up dead fish. August 10, 2014.

7 Figure 5. Bucket of fish collected during e Nor River fish kill clean-up on August 10, Figure 6. A sample of e four species of fish collected in Nor River.

8 APPENDIX NORTH RIVER FISH KILL NECROPSY RESULTS Atlantic Veterinary College

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