Are these Daphnia:
Throat Pump Question.....
- Thread starter Ron McNeal
- Start date
I would say yes.
Follow up question: If Rod and Dean are correct then I'd like to know if water fleas/daphnia come in different sizes (sub species? - I can't tell for sure what size the daphnia are in Ron's photograph). I tend to think of daphnia as more orangish in color. But WDIK?
Bambooflyguy
Legend
I’ve seen them from pale white, greenish, orange to red. Up close they look kinda like tiny scuds to me…..
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There are not as many species of daphnia as there chironimidae, but they do differ about the same. Different colors do exist.
Most of my samples so far this year look a lot like that. It’s early season.
Yeah........ I should have added something to the photo to show scale. FWIW, the white "dish" is the lid from a plastic mayo "jar."......
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Daphnia and other copepods and other small critters our common in our lake. Daphnia is the one most commonly found in out throat samples. While also small their size varies as they grow towards maturity, there can be multiple generations of daphnia during the course of year. Their color can vary from pale whitish/greenish to dark olive. Don't generally see orangish color individuals except stomach samples.
I suspect that generally trout feed on them by swimming through the water/clouds of critters with their mouth open allowing the water to flow over their gills where the closely spaced gill rakers separate the daphnia from the water and swallowed. As a particular matter once a rainbow trout grows beyond 16 inches or so due to increased spacing of their gill rakers the larger fish become more inefficient in in filtering the daphnia from the water.
Generally, daphnia are a great food source often being a critical found source for the smaller trout and during the winter period when many other food sources are scarce. In productive waters, especially of single species trout water it was not uncommon to find the stomachs of rainbows "stuffed" with daphnia. In some cases I have seen where the stomach contents of a single fish filling a shot glass.
curt
I suspect that generally trout feed on them by swimming through the water/clouds of critters with their mouth open allowing the water to flow over their gills where the closely spaced gill rakers separate the daphnia from the water and swallowed. As a particular matter once a rainbow trout grows beyond 16 inches or so due to increased spacing of their gill rakers the larger fish become more inefficient in in filtering the daphnia from the water.
Generally, daphnia are a great food source often being a critical found source for the smaller trout and during the winter period when many other food sources are scarce. In productive waters, especially of single species trout water it was not uncommon to find the stomachs of rainbows "stuffed" with daphnia. In some cases I have seen where the stomach contents of a single fish filling a shot glass.
curt
On a side note, daphnia should not be ignored. I’ve heard people complain about finding daphnia in throat samples, thinking that the fishing will be a bust. If the fish are on daphnia, it is likely that the daphnia is all that is available.
They will eat other offerings, but you have to find where the fish are targeting the daphnia. Daphnia will often times populate areas of a lake where we don’t normally fish. We mostly fish the Littoral zone of a lake (where light is able to reach the bottom of a lake and support primary producers). Daphnia on the other hand will live comfortably in the pelagic/open water zone or even into the Profundal zone of a lake (below light penetration).
Daphnia will move up and down in the pelagic zone as light penetration changes throughout the day. They are photo sensitive and will move deeper with more light penetration. This the shallow early, deeper later rule of thought. Sometimes though this isn’t true.
The first time I experienced a visible daphnia concentration was on Pass lake in February. @Nick Clayton and I were fishing a deep area within the littoral zone at the far end of the lake most of the day with some success. He needed to leave early so I rowed him back to the launch. Wind was fairly normal, but pushing up against the launch. We could see what looked like an algae bloom next to shore as we approached. We were with another fisherman who was in a float tube and closer to the water who asked, “What are all these little bugs?” Upon closer inspection I noticed that the algae was a massive cluster of daphnia right at the surface. The entire cluster was about 15’ off the shore, about 10’ across, 4’ deep and it stretch about 100 yards down the shoreline.
I dropped Nick off, rowed back out, anchored and dropped a micro leech 3’ under an indicator right into the cluster. I landed 5 bows before Nick left the parking lot. I kept working the cluster all the way down the shoreline, picking up several more fish until I too needed to leave. I used the same pattern the entire time, but I don’t think the pattern mattered at all, those fish were hungry and presented with a larger meal, they were happy to take it.
Through more times I’ve found visual clusters of daphnia, and all three times fish were concentrated on the clusters. @troutpocket and I found two areas of a lake earlier this month and both areas were by far the most productive areas of the lake.
They will eat other offerings, but you have to find where the fish are targeting the daphnia. Daphnia will often times populate areas of a lake where we don’t normally fish. We mostly fish the Littoral zone of a lake (where light is able to reach the bottom of a lake and support primary producers). Daphnia on the other hand will live comfortably in the pelagic/open water zone or even into the Profundal zone of a lake (below light penetration).
Daphnia will move up and down in the pelagic zone as light penetration changes throughout the day. They are photo sensitive and will move deeper with more light penetration. This the shallow early, deeper later rule of thought. Sometimes though this isn’t true.
The first time I experienced a visible daphnia concentration was on Pass lake in February. @Nick Clayton and I were fishing a deep area within the littoral zone at the far end of the lake most of the day with some success. He needed to leave early so I rowed him back to the launch. Wind was fairly normal, but pushing up against the launch. We could see what looked like an algae bloom next to shore as we approached. We were with another fisherman who was in a float tube and closer to the water who asked, “What are all these little bugs?” Upon closer inspection I noticed that the algae was a massive cluster of daphnia right at the surface. The entire cluster was about 15’ off the shore, about 10’ across, 4’ deep and it stretch about 100 yards down the shoreline.
I dropped Nick off, rowed back out, anchored and dropped a micro leech 3’ under an indicator right into the cluster. I landed 5 bows before Nick left the parking lot. I kept working the cluster all the way down the shoreline, picking up several more fish until I too needed to leave. I used the same pattern the entire time, but I don’t think the pattern mattered at all, those fish were hungry and presented with a larger meal, they were happy to take it.
Through more times I’ve found visual clusters of daphnia, and all three times fish were concentrated on the clusters. @troutpocket and I found two areas of a lake earlier this month and both areas were by far the most productive areas of the lake.
To expand a bit on Ira's post above. During the night (especially during the longer winter nights) winds tend to blow the surface water and daphnia to the far shoreline. If there are steady winds from the same direction for several days the majority of the daphnia will end up on the opposite side of the lake. If I plan to fish that time of year, I follow the weather for several days before fishing to help decide where I will fish. If a prevailing wind shifts for a day or two the hot shoreline will also shift.
Under the above conditions if fishing under an indicator Ii fish with two rods and two flies constantly experimenting with the depth to stay with the fish as they follow the daphnia down. Another tactic that has served me well is to fish with something like a soft hackle covering a lot of water with aggressive retrieve or if trolling a pretty quick pace.. The goal to get a reaction bite for these inactive fish and the more fish I show my fly to the more I catch.
Curt
Under the above conditions if fishing under an indicator Ii fish with two rods and two flies constantly experimenting with the depth to stay with the fish as they follow the daphnia down. Another tactic that has served me well is to fish with something like a soft hackle covering a lot of water with aggressive retrieve or if trolling a pretty quick pace.. The goal to get a reaction bite for these inactive fish and the more fish I show my fly to the more I catch.
Curt
Flymph
Life of the Party
I have developed (probably copied from some article) a daphnia fly that works, "sometimes", quite well, early in the season if (as stated earlier) you can find the concentrated areas. A large, olive, leech pattern, dotted with bright orange paint throughout the body and extended strands. Simply tie in your favorite leech yarn/dubbing and tease out a lot of strands. Add the dots and toss to trout.
Nevertheless, Ira is probably right in that any good bug would likely interest the hungry trout.
Nevertheless, Ira is probably right in that any good bug would likely interest the hungry trout.
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Coho
Steelhead
Super interesting! Thank you for posting that. Learned something new.