Lampreys - Control & future

[LongLine]

Here's a video by GLFC/USGS on Lamprey Control program in Great Lakes. Posted 11 months ago.

 

 

 

Here's some "cliff notes"

LAMPREYS:
- There are 4 native Lamprey's.  Sea Lamprey is invasive and much larger
- Lampreys have 100,000 eggs of which 10% are viable. They die after spawning.
- Males make the nest and females are attracted to males by scent.
- They do not necessarily return to their natal streams to spawn.
- They also attack Perch, Walleye, Bass and Pike.
- 6 out of 7 attacked fish die. If not directly from wound, then from infection.

TREATMENT:
- Treatment is at nesting sites, which are located by electroshocking.
- pH, Alkalinity, temp and O2 are measured first.  If conditions not met then treatment is deferred.
- TFM liquid used for typical streams. Bayluscide crystal used on rivers. TFM blocks used on real small creeks.
- Liquid treatment requires constant monitoring and is applied over a 12 hour period.
- Physical barriers block upstream migration. Lampreys can't jump over 18".
- Traps are for migrating adults but are the least effective control.
- Lake Ontario population spiked in 2023 as traps caught "thousands" of Lampreys. GLFC playing "catch up" since.

FUTURE TREATMENTS:
- Sterilization has had very limited testing. Only for males.
- Pheromones (scents)
1. Attractants: To improve trap capture.
2. Repellants: To prevent migration.
3. Antagonist: To prevent females from finding nests
4. Predator: To scare them away. Basically the smell of dead Lamprey.

QUESTIONS & ANSWERS:
- Lampreys do not return to natal streams like salmon.
- Nontarget specie affected by TFM are Mud Puppy (salamander) and small Lk Sturgeon. 
- Lake Sturgeon were removed from treatment streams and held in ponds until TFM treatments finished.
- Lab testing of TFM used a small Bluegill and small trout. (video shows trout laying on its side)
- Whether Lampreys can build up resistance to treatment is being studied via DNA analysis. No results observed yet.
- Of their $19.6 million budget, $13 million went to Lamprey control. (that year)
- Sterilization limited to small ponds due to potential influx of unsterile males migrating in larger lakes. 
- TFM not effective below 6C (42.8F)

- Warming water will "probably" cause lamprey to spawn earlier in season.
- Walleye may opportunistically eat them but natural predator unknown.
- Lamprey specie over 300 million years old and were most abundant on west shore of Europe but now endangered there.
- Lamprey considered a delicacy in UK.  "Lamprey Pie" is basically a "stew."  

 

(If you can't view it, simply log onto google or a gmail account on another tab)

[rolmops]

Thank you for putting this up.