Coho Fry of the Year
The colder than usual winter we experienced on the Lower Mainland meant that I would have to wait extra-long for the Coho fry to emerge from the gravel this year.
After visiting MacKay Creek in late March and seeing dozens of tiny fry, I couldn't help myself but visit Mosquito Creek every 2nd or 3rd day until I was finally able to spot some fry.
The fry were spotted in the Fell Channel a day or two before the juvenile trapping with Scott & Sandie on April 4th/5th. I was quick to point out the exact spot I had seen them with Scott & Sandie on the day of the trapping, April 4th. As a group we were lucky enough to see a couple in that very same pool, but nothing like the numbers I was seeing throughout MacKay Creek.
I was surprised to see any year of the year in the Fell Channel, as I had not seen a spawning pair in there during the fall. I suppose it is quite possible they evaded my eyes, but another strong possibility is these fry had been swept into the intake of the fell channel. This would mean they were actually from the main stem of Mosquito, or had been pushed down all the way from Thain Creek.
Either way it was a great find and they sure looked happy to be in the slower-moving channel environment.
Thain Creek & Mosquito Main-Stem
The channel where I had seen four adults was the Griffin Channel, and the possible redd (nest) Sandie had helped identify still showed no signs of successful yield all the way through to around April 14th.
I decided to go to check out an area of Thain Creek where I had seen plenty of Coho spawning in the fall. First stop was the jimmy-rigged bridge over the creek that trail go-ers maintain. Sure enough in the back-eddys in the nearby area of the bridge I spotted some Coho fry of the year.
This was a good sign, but I knew there would be plenty more where I was headed. Sure enough the holy grail of spawning pools had produced a great number of fry. In this particular area of creek I was able to see around 20 fry of the year, which was about the number I had expected to see. I am hopeful a large majority were able to avoid my eyes though. I had seen 6 spawners in this area, so only 20 fry would be a huge dissapointment if that was all that had survived.
As I made my way down the trail, I decided to check out the West Alcove on Mosquito Creek, on my way to the alcove opening there was a large deep pool of slow moving water, protected by a large boulder. I didn't think I was going to be so lucky as to see any fry in the mainstem as the water was still fairly high, but protected from the torrent there were 3 fry of the year hanging out in plain sight! I continued down only a couple feet further to survey the alcove itself, but was unable to spot any fry in the alcove itself.
On the morning of Saturday April 15th I decided to check out the Griffin Channel. Sure enough, just above the top habitat pool I spotted my first pair of fry in the Griffin Channel. This was a hugely positive sign as that now meant I had seen Coho fry of the year in both channels, Thain Creek, & the main-stem of Mosquito Creek.
I continued down the channel to see if there were more fry around the redd, but yet again not a fry in sight. I walked a bit further down the channel and was able to find two more areas with a few fry. This area of the channel is mostly fast flowing, but where the fry were spotted was in protected still water. The substrate was a dark muddy color and the fry blended in very well. By my estimate I had seen approximately 8 fry all together in the Griffin Channel.
It was hugely positive to see fry in the Griffin Channel, but even in these wonderful channel habitats it seems the survival rates from egg to fry are extremely small.
MacKay Creek Comparison
Firstly, I would like to thank everyone involved with the restoration and enhancement of MacKay Creek, including the recent estuary revamp. It is truely a gem in the urban world in which we live and all the hard work is definitely starting to show.
After walking MacKay a couple times in April, I really wish we were so lucky as to have every creek in North Vancouver as healthy as MacKay... - Maybe one day.
One of the first things you might notice when walking the trails of MacKay Creek, is the amount of woody debris in the creek itself. If you were to compare MacKay to pretty much any other creek on the North Shore, especially Mosquito, you will find there is really no comparison. Most creek beds now run debris-free, but MacKay Creek is an outlier.
I am beginning to think this woody debris has a deeper impact on creeks than we currently understand.
You can probably tell I am hinting at something, if so you are right.
In just a few trips I was able to see, without a doubt, literally thousands of Coho fry on MacKay Creek. The results in 2017 have been phenomenal! I have been able to identify two particular areas of the creek where shoals, yes shoals, of fry hold up.
The number of fry in these shoals come close to breaking the 50 mark. As one walks past one of these areas in particular, a 6-ft long section of streambed seems to move in synchronization!
Fry of the year in these numbers are so rare, which leads to another comparison in which there really is no comparison. No other small creek on the North Shore has the number of fry as does MacKay.
Don't get me wrong, I am extremely excited to see fry on Mosquito in the numbers I have seen. I do however think MacKay Creek should be used as a model, an example of sorts, which all the creeks on the North Shore should strive to become.
I would recommend maximizing this video to full screen and keeping an eye on the bottom left area of the screen as that is where the most action happens.
I am definitely not doing Apple any favors by selling their iPhone 6 camera, but as I am sure you can understand these little guys are super camera shy. If you get too close they'll disapear. This was the best footage I was able to get.