Genetics Study FAQ

October 18, 2016 Posted by: David Kopshever

409 Beadnose being darted for the Genetics Study
409 Beadnose is darted by Ranger Michael Saxton. NPS Photo/D. Kopshever. 

If you've been watching the bearcams on, you might have noticed bears being darted along the Brooks River. That activity is part of Ranger Michael Saxton's Brown Bear Genetics Study. Learn more about the study with the FAQ below. 

1. What do you hope to accomplish with the study? 

The primary aims of the study are to evaluate gene flow throughout Katmai and the surrounding area and examine local population structure. One question we have had is how connected bears on the coast of the park are to those in the interior at places like Brooks Camp. By looking at the DNA of bears in both locations we can see if there is active gene flow across the Aleutian Range. The mountains by themselves would not likely prevent movement back and forth, but the lack of resources in the mountains may result in bears being unwilling to leave the abundant food on the coast or in the interior to cross to the other side.

The ability to create a pedigree of bears at Brooks Camp is not one of the primary objectives of the project but if the project is repeated every five years or so it may be possible to follow up with some very exciting behavioral genetics work. That and the popularity of determining the parentage of the bears is why that is a current goal as well.

2. What is the level of discomfort on the part of the bears when darted, what would you liken it to?

From the reactions that I have seen, ranging from no response at all to running 20 yards and huffing, I would say that it is similar to being stung by a bee (assuming of course you are not allergic to bees, which I can assure you the bears are not allergic to the darts).

3. What are the risks involved, and what is the level of those risks?

The level of risk is extremely low in a study like this, as the darting occurs at close range and using a dart gun with variable pressure it is easy to make sure we do not cause any permanent harm to the animals. With that said, however, there is always some risk when shooting is involved. The primary risk is that a dart hits a bear in the wrong spot and penetrating the abdominal cavity, damaging internal organs. The primary ways to minimize the risk is only to take shots when you are not rushed and the circumstances allow for a good shot. Additionally, our dart gun allows me to adjust the pressure depending on the range of the shot I am taking, further reducing the risk of penetration.

4. When does darting take place?

Darting takes place anytime I am able to when I do not have to worry about chasing a bear into people or placing the bear in a dangerous situation. In July this meant that darting only occurred at the Falls and Riffles area as there were too many people on the ground in other locations, but after camp closed in September I have been darting much more in the lower river, both from the platform and from the bridge when necessary. Usually I will not dart when I am on the ground with the bears as that may place me in a dangerous situation, but there are some circumstances, such as if I have a building or vehicle nearby, where I will do that as well. I will also only dart when it is reasonably light out so I can be sure of my shot, and I try not to dart bears that are actively fishing as I don't want to discourage them from eating at such a critical feeding location.

5. How does the dart gun operate?

The dart gun is powered by CO2, there is a gas cartridge attached so after I insert the needle I add the appropriate pressure for the distance I am shooting. Once the dart hits a bear they are designed to fall out quickly, either immediately after the impact or shortly after as the animal begins to move. What has been known to happen occasionally is that hair may become pinched between the needle and the dart so it sticks to the bear longer than normal. This happened with one dart I shot at 83. He walked off with the dart still hanging from him and we were not able to recover it as a result (he was seen a short while later without the dart so it fell off just after we lost sight of him). 

6. What bears have been darted to date - successfully vs unsuccessfully?

Unknown Subadult

7. How many bears do you hope to dart?

I hope to dart all of the bears that I can in the Brooks River area. In reality that will likely mean I am able to get around 30 to 40 bears between this year and next. This year was pretty slow as we were still figuring out the best techniques and materials to use but Fall has been much more successful than July, so I hope that next year will be productive.

8. When will data be analyzed?

Analysis will begin this winter when I am back in WA, but will likely not be complete until at least Summer of 2018. Largely this is because I will still need to incorporate samples that are collected next year.

9. When will resulting information be made public?

The parentage analysis will be made public as we determine relationships but realistically most of this will not be made public until 2018 or 2019 as we will have to wait for analysis to be complete and then publication. The parentage though is not a part of the primary study so it will be released informally via as we get results (which may still not be until 2018).


Brown Bear, Brooks River, science

Last updated: October 18, 2016

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