Overharvesting dragonfly nymphs...

[navigator37 0]

Just came across this article on an occurrence

in Oregon around the Todd Lake area that took place in the

past years.

It's an interesting little read that shows how quickly people can

damage a simple niche of a lake ecosystem.

In this case, how quickly actual dragonfly numbers in a lake area can be depleted

over such a short period of time by over harvesting.

Dragon nymphs were being sold by the thousands for 12-18$ per dozen or so

being collected from lakes there. Shame.

Dragonfly report

[JSzymczyk 0]

No Updates since 1999?

 

IMO habitat destruction was probably the culprit. "Rolling over logs" etc plus wading all through the best areas, probably those area with weed growth and an organic matter bottom. Damn those professional guides!!! And fishermen in general!!!

 

"the uniqueness of the Todd Lake populations may be lost" blah blah blah that is SOOO typical and also so unprovable, of a university researcher working on a master's or doctorate... I'd like to see what has happened in the past 10 years. Good God if this guy would have somehow tied in Global Warming into his reasoning for population changes, he'd have been rolling in Taxpayer dollars from government research grants.

 

I wonder what the natural population cycle is like for that area too. Every living thing goes through peaks and troughs of population density in a given area. Some are extremely noticeable, like the 11 year cycle of Ruffed Grouse in the northeast, others are poorly understood.

[redietz 0]

No Updates since 1999?

 

IMO habitat destruction was probably the culprit. "Rolling over logs" etc plus wading all through the best areas, probably those area with weed growth and an organic matter bottom. Damn those professional guides!!! And fishermen in general!!!

 

"the uniqueness of the Todd Lake populations may be lost" blah blah blah that is SOOO typical and also so unprovable, of a university researcher working on a master's or doctorate... I'd like to see what has happened in the past 10 years. Good God if this guy would have somehow tied in Global Warming into his reasoning for population changes, he'd have been rolling in Taxpayer dollars from government research grants.

 

I wonder what the natural population cycle is like for that area too. Every living thing goes through peaks and troughs of population density in a given area. Some are extremely noticeable, like the 11 year cycle of Ruffed Grouse in the northeast, others are poorly understood.

 

 

I'm questioning it in the same way. I'll allow for the possibility that it may be true, but a single, ten year old study doesn't convince me, and certainly didn't show a causal effect. It could be cyclical, it could be climate related (too hot/cold/dry/wet), there may have been nearby logging, any number of causes.

 

OTOH, I don't have any problem with the study being done, and if there were good solid evidence (and this isn't it) that overharvesting is is having a major negative impact on the population, then regulation may be in order.

[Old Hat 0]

Many of the lakes in the Central Cascades of Oregon were harvested for dragonfly nymphs. I have fished Todd Lake numerous times along with Crane Prairie Reservoir which was another popular nymph harvesting spot as I lived in the area for about 12 years. Most of the lakes in the area are great producers of trout and other fish and today the dragonfly populations are alive and well. I don't think much illegal harvesting goes on anymore as the population of people and fishers on these systems provides quite a deterrence, as well as a diminished market and general public education. The places aren't as isolated as they were just 10 years ago. Also the impact of nymph harvesting is well known among many residents who frequent the area and it is frowned upon greatly. Todd Lake is a small system and could easily be affected by overharvesting but there are so many lakes in the area that these lakes can easily be reestablished as they seem to have been. Anyhow, the lesson seems to have been learned and most of water now is very productive and at the mercy of weather conditions. Now if we could just keep people from introducing invasive species (bass, stickleback, chub and other bait fish into pristine native trout water that would be :thumbup: but until then :wallbash:

[flyderaght 0]

Intersting. I know in BC if your caught using insects as bait it's something you can be charged for. I've seen people do it, and it does bring the fish up that's for sure!

[upstate tj 0]

keep reedin keep lernin.. sumpin new every day