MILLARD- PIERCY WATERSHED SMOLT COUNTING SUMMARY
Coho salmon smolt counting was conducted on Millard Creek mainstem and Tributary 1 of Piercy Creek from April 18 to June 7 and on Millard side channel from April 18 to May 26.
Volunteers counted coho smolts, fry and other species once per day, typically in the mornings. Samples of fish were measured and, in some cases, weighed as well during most of the counting period. Accumulated debris was cleaned off the screens as necessary.
This was a very unusual year for stream water levels because of the limited rain during the period of counting. The only significant rain event was on May 14 and it was very modest with only 6.8 mm recorded at Comox airport. However, it was enough to result in an increase in coho smolt counts at all three sites for several days. Apart from that event, water levels continuously declined to very low levels. Water temperatures were similar at all three sites ranging from 6 or 7 degrees C at the beginning of the sampling period to 13-15 C at the end.
The coho smolt count at Millard mainstem was only 726, well down from 2,991 in 2018 and the lowest since 2007. A total of 463 coho fry were counted which is a relatively high number compared to recent years. Other species recorded were 3 trout, 114 sculpins, 2 lampreys and 52 crayfish. Ten coho smolts and 2 coho fry were found dead.
The Millard side channel count was only 41 coho smolts, well down from the 2018 count of 320 but not far off the 58 total for 2017. There were also 6 coho fry and 6 crayfish. Greater numbers of coho fry were sometimes observed swimming in the pool immediately upstream of the counting fence. The water level in the holding box was very low and declined to only 3 or 4 centimeters in depth by the time counnting was discontinued.
The Tributary 1 of Piercy Creek count of only 168 coho smolts was well down from the 2018 count of 744 and the lowest since counting started in 2015. Coho fry totalled 165, cutthroat trout 7 and crayfish 33. Mortalities included 1 coho smolt and 3 coho fry. Good numbers of coho fry were observed swimming both upstream and downstream of the counting fence.
It is not clear if the low numbers of coho smolts counted in 2019 is the result of the lack of sufficient rainfall to trigger seaward migration or due to poor survival from the egg to smolt stage. If the former, there should still be smolts within the watershed waiting to migrate to the estuary