Capture-Mark-Recapture

USFWS Fish Biologist Nolan Banish explains the data collection process

Another week, another federally listed threatened or endangered species! This past week we were introduced to the threatened fluvial bull trout (Salvelinus confluentus) of Deming Creek. The bull trout of this particular region fall within the Upper Sprague River core area of the Klamath Recovery Unit. Deming Creek is believed to support the largest local population of the species in the Upper Sprague River core area, with high relative abundance, quality habitat, and a stable population number. Deming Creek is also unique in that it is free of nonnative brook trout (Salvelinus fontinalis), a congeneric species that competes and often hybridizes with bull trout.

Jenny measures the length of a bull trout capture
Red band trout capture

Our goal for the next two weeks is to determine just how effective backpack electrofishing is in achieving a high recapture percentage in bull trout, and therefore a higher confidence interval in population size. We are sampling two hundred meter reaches of Deming Creek in two day increments; the first day being the capture and mark portion of the study, with the second day acting as a 24 hour buffer for the fish to re-acclimate to their habitat. The second day we will conduct the same survey of the reach, walking upstream and e-fishing and capturing any fish we see. By comparing the recapture counts to the previous day’s capture numbers, we get a percentage of our productivity, with that goal to better understand the confidence interval of our population estimate.

Blocknet set up

After about an hour and a half drive east of Klamath Falls toward Gearhart Mountain, we entered Winema National Forest, and the location of our survey site. We began by setting up an initial block-net that spanned the creek from bank to bank. We configured another identical net two hundred meters upstream from the first with the purpose of maintaining the same density of fish within the two nets for the duration of our sampling. Starting at the lower block-net, the four of us (Nolan, our mentor; Jenny; Brianne; and I) began the arduous journey across the slippery rocks and deceptively tumultuous riffles in search of any flash of the white underbelly of a trout that has lost equilibrium due to the electric current.

Jenny acts as primary netter while Nolan wears the electrofisher backpack

Within the first twenty seconds we’d caught our first fish: a 124mm red band trout! The next three hours entailed rotating of tasks between the four of us — electrofisher, first netter, second “ghost netter” and bucket holder — the latter being the most awkward of the four as you are the one to transfer each catch to the bucket while protecting the bucket from the imminent and inevitable dangers of capsizing through your own demise due to the slippery creek bottom.

Capture of different age classes of red band and bull trout

I think my favorite role is that of the primary netter, but as Jenny and I were reflecting on how reminiscent this week has been to our pasts of playing high school and college sports, I was reminded of how gratifying and crucial each role is to the greater purpose of the team. The thrill of netting a >200g red band or bull trout is palpable as Brianne locates the convulsing fish, Jenny lunges forward towards the anode for it and I shriek with excitement when I realize it’s a recapture from the day before as I gingerly transfer it to my bucket.

Fremont-Winema National Forest
Our tent set up for the week’s work

Dark, Dank, and Claustrophobic

USFWS biologists stand within Valentine Cave

This week we were lucky enough to meet up with Katrina Smith, the Natural Resource Specialist from Lava Beds National Monument. Only a 40 minute drive drive south into California from our headquarters in Klamath Falls, this was a scheduled office field trip — an opportunity to learn more about the bat populations of the area and the cultural heritage of Tule Lake National Monument (also historically known as Camp Tule Lake). For the respect of the history of Camp Tule Lake and the incarceration of thousands of Japanese citizens and non-citizens, I will write a separate post in the future that is dedicated to this dark time in history.

Jenny helps set up mist nets outside of Camp Tule Lake structures.

A few months back we had worked with Katrina at Tule Lake assisting in bat mist netting, so the opportunity to hear more about her work in Lava Beds was especially compelling. She explained that there are fifteen species of bats found within the monument, and that species monitoring included winter hibernacula surveys, spring mist-netting, and acoustic surveys. There are three stations set up in Lava Beds that use stationary acoustic monitoring to give occupancy model information for population counts of each species; Katrina mentioned wishing the Park Service had access to more, but informed us that each station costs upwards of $2,000 and requires active data analysis in the form of paid employees, of which the monument is lacking in during winter months especially. The three species unanimously found at each site included the silver haired (Lasionycteris noctivagans), yuma (myotis yumanensis), and pallid (antrozous pallidus) bats.

Technicians prepare the acoustic monitor, Sonobat.

Many of us had heard mention of white-nose syndrome, a fungal disease that has affected and killed millions of hibernating bats throughout North America. Until this past year, the disease had not been recorded in any bats in California. However, this past spring in Plumas County (near Lassen Volcanic National Park) four bats have since tested positive for low levels of the fungus, marking the spread of the disease to this part of the country.

Katrina takes a swab sample of a myotis volans.
This particular bat had very healthy and intact wings.

The bats we mist netted for at Camp Tule Lake this April were not affected by white-nose syndrome, but biologists continue to monitor the populations living in the abandoned buildings left over from Japanese internment and incarceration during World War II. Much like the risk to specific bird species in the area, migratory bats also continue to face threats of habitat loss, wind energy, and disturbance of roosting sites by the public. Katrina mentioned the need and desire to better understand the patterns of movement in bats as they migrate, and encouraged us all to come volunteer at any point in the future!

Some of the spaces required crawling to get through.

Our day continued with two cave tours from one of the Park geologists took us deep into Valentine Cave and Scull Cave! We learned about the formation of lava tubes and a little more about the research being done regarding climate change and the unique environments within each cave system.

Each cave boasts complex bacterial communities
The cooling of lava creates different textures on the cave floors.
The entrance/exit of Skull Cave.
Panoramic view of Lava Beds National Monument

The Wolf Pack

“Remote camera photo of OR7 captured on 5/3/2014 in eastern Jackson County on USFS land. Photo courtesy of USFWS.” https://www.dfw.state.or.us/Wolves/Packs/Rogue.asp

No, we haven’t seen or heard any wolves—but they are here! This week our work has taken a full 180; we’ve transitioned back to our diurnal habits and away from fisheries work. We’ve pivoted to helping out two female biologists at Fish and Wildlife, and we’re diving head on into two very different endangered species from the Shortnose and Lost River suckers: the Grey Wolf (Canis lupus) and the no less majestic, and significantly underrated Applegate’s milkvetch (Astragalus applegatei.)

Astragalus applegatei flowering

We began the week on or new project getting to know how to ID the astragalus, in hopes that by the time we were out in the field monitoring polygons from previous years we’d be able to get through each plot relatively efficiently. Using our handheld GPS to mark the outermost points to each polygon, we split the area into transects that we would then visually scan for individual plants. Jenny, Brianne, and I are working together to formulate a sampling plan for those polygons that contain more than 11,000 individuals. More on that later!

Jenny excitedly flags separate Astragalus applegatei plants!

I sat here trying to think of a clever transition between astragalus and wolves, but after five minutes of staring at the cubicle wall, I found that there really is no easy segway. So I’ll just dive right in!

2016 pups from the Rogue River Pack captured by USFWS camera trap. https://www.dfw.state.or.us/Wolves/Packs/Rogue.asp

The Rogue River Wolf Pack is led by Alpha male OR7, named such as he was the seventh wolf to be radio collared in Oregon. Born into a litter in Northeast Oregon, OR7 left the pack he was born into, wandering as far south as Lassen, California—becoming the first known wolf in California since the last wild wolf was shot in the very same area in 1924. Eventually OR7 made his way back north into the east Cascades of southern Oregon, where he’s been denning and raising pups with a female (also linked to Northeast Oregon) since 2014.

Brianne and Jenny taking a pause between fladry breakdown

As we drove to the site, we were reminded that the pack dens just six miles from the property, and that their range spans across the county line between Jackson and Klamath Counties. The ranch itself is found just northeast of Klamath Lake, in Jackson county, and because the pack has chosen to make its denjust east of Klamath Falls, ranchers in the area are inevitably affected by the range the wolves wander as they hunt. As a result, we’ve been spending time de-commissioning fladry (wire line fitted with red flags that flap in the wind that have historically been used to deter wolves from entering onto ranch land) and electric fencing for a ranch just southwest of Crater Lake. Both had originally been installed last year by Oregon Fish and Wildlife (ODFW) and US Fish and Wildlife (USFWS) in response to calf depredation on this ranch (just last year three calves and one of two Tibetan mastiffs were killed by the pack.) Now that the landowner is rotating his cattle to another field, the fladry is no longer needed and we were the lucky ones called upon to remove it!

Current range of the Rogue River pack. Image courtesy of Wolf pups of the Rogue Pack. Image captured using an USFWS camera trap on July 12, 2016. Courtesy of https://www.dfw.state.or.us/Wolves/Packs/Rogue.asp

All in all, it was pretty labor intensive work, seeing as the fencing spanned the area of the property, but we were able to roll up the entirety of the flagging, collect the motion detector lights (also used to deter the pack at night), and pull the hundreds of fiberglass posts the wire line was attached to, all before the workday ended! Needless to say, even with gloves on, those fiberglass shards found their way into the palm of your hand. But despite the long day, we feel pretty lucky to be involved with the project.

A Golden-rod crab spider (Misumena vatia) devours a butterfly on the ranch property.

We also found a killdeer (Charadrius vociferus) nest on site at the ranch property. Photo credit: Brianne Nguyen

Next week we’ll be conducting more milk vetch surveys, and heading out to check camera traps for the pack; we’ll be sure to update you if the wildlife cameras have captured any more exciting photos!

Rising with the Suckers

Crater Lake, located just an hour and a half drive north of Klamath Falls

Just as Hungry in the Night as in the Day

I’m currently on my second midnight snack. I guess you could call it a midnight meal at this point because we’ve been living the nocturnal life for two weeks now—start work at 2am, return home around 10am. The first few days getting acclimated to this schedule were pretty tough; one particular morning involved falling asleep in the waiting room of the BLM office, but now I guess you could say we’re thriving.

Brianne gazes longingly into an sucker-less bucket

Intros aside, greetings from a clear starry night in Klamath Falls! I’m nice and cozy writing this blog post back in the US Fish and Wildlife office. It’s 5 am on Friday morning of our second week. This morning started off with the three of us piling into the USFWS truck to drive thirty minutes to Modoc Point where the bridge over the Williamson River marks the catch point of Lost River (Deltistes luxatus)/Shortnose (Chasmistes brevirostris)/Klamath Large Scale (Catostomus snyderi) sucker larvae we will be collecting for the next few weeks into mid June. We deployed our two separate plankton nets in four sets, with a twenty minute window for larvae to collect in between each retrieval. It was below freezing and lightly snowing when we started, so that twenty minutes of waiting for larval accumulation took place in the car with the heat blasting. When our timers went off we rushed back to our nets with corresponding buckets filled with Williamson River water. We pulled our nets up and gingerly unscrewed the base of the two, using our headlamps to illuminate our samples. We were looking for translucent,10mm long larval suckers, but collection has purposefully been scheduled for just before the peaks of larval activity are to occur, in hopes that we won’t miss our opportunity to catch our goal of 30,000 larvae this season. As a result, last week we ended up with buckets full of plant life, and many different kinds of macroinvertebrates, mostly mayflies and stoneflies.

Williamson River reflection

Why suckers? Why 2am? Why larvae?

I know, so many questions! The shortnose and Lost River sucker species have been federally listed as endangered species since 1988. With both species endemic to the Klamath Basin, the habitat degradation of riparian areas and manipulation of waterways in the the last hundred years have negatively impacted water quality and spiked phosphate and other nutrient levels in Klamath Lake. The situation has gotten so bad that the juvenile suckers are no longer able to reach sexual maturity to bring population numbers back up to a stable level.

That said, for whatever reason my self-illustrated initial mental image of these fish had them as pretty puny and short-lived. My low expectations for the species were blown out of the water (literally) when we were lucky enough to observe USGS studying adult suckers spawning in the cold springs of the rocky eastern shores of Klamath Lake. We learned that adult suckers are supposed to live between thirty to forty years, and can be almost three feet long! I realize that size should not be an indicator of the amount of respect I have for a species, but I was in awe of their size and beauty that day on the lake.

USGS handles an adult Lost River sucker

So that should get us caught up—USFW has undertaken a Juvenile Sucker Rearing Program involving the larval capture of days old juvenile suckers for the purpose of raising them in tanks and ponds located at a shared property called Gone Fishing, just about three miles north of the Oregon/California border as the crow flies. The larvae begin to hatch and float/swim downstream early May through mid June, and are most active around 3am, hence our night work for the next few weeks!

Measuring and PIT tagging suckers before their release into Klamath Lake

In two to three years these larvae we’ve caught will have been steadily maturing in outdoor ponds on the property. Around this time they’ll either be PIT tagged or radio tagged and released into Klamath Lake in the hopes to add to the population of sexually mature adult suckers.

Checking the security of the Klamath Lake soft-release nets

Fitting drains for the 150 gallon tanks

So here we are, back in the office and waiting for the sun to rise so we can head over to Gone Fishing. This past week we’ve spent a majority of our time at Gone Fishing, preparing various sized tanks for the sucker larvae we will be raising to juveniles (about 2 years). Prepping includes, but is not limited to drilling through the twenty-four 150 gallon fiberglass tanks and fitting each with a drain that connects to a mainline, as well as cutting and constructing the PVC piping that fits and fills each tank. There has also been a fair amount of creative interpretation/freedom for how the three of us wanted to construct a table that would support four individual inverted five-gallon water jugs, which would act as our brine shrimp hatching vessels, eventually serving as sustenance for our growing larvae!

Jenny and Brianne fit one of our 150 gallon tanks with a drain pipe

Getting a Better Sense of Place

Mt McLoughlin’s reflection into Klamath Lake

Honestly, my favorite parts of these last few weeks have been the opportunities we’ve been given to learn about this place and the work Fish and Wildlife is doing for the sake of the Endangered Species Act.

Mt McLoughlin and some transportation

Biking to work every morning has helped us navigate this town with ease, while cruising the lake during our first week’s afternoon hours in the radio telemetry boat, and watching the sun come up over the hills as we pull in our last larval set from the Williamson River Bridge almost makes me never want to go back to daytime work.

Larval collection sunrise

I feel I’ve gotten my bearings around town as well as an understanding of what makes Klamath Falls so special. The stillness of snowy Mount Mcloughlin’s reflection on the lake is broken by the Clarks Grebes “rushing” mating dance—a graceful but intense side-to-side stretching and bobbing of the male’s and female’s necks followed by a simultaneous “running” on the lakes surface before both birds dive below the water. White pelicans fly overhead and it sinks in that we are here, and we too are lucky to call this lake home for the next five months.

White pelicans about to take flight

Extra Extra! Update! Larvae waits for no woman

Larval Collection sample vid

Two weeks later: success! We’ve now been USFW for four weeks and we’ve got some news! Last week we had switched back to normal diurnal hours to complete an online electrofishing training, and the larval counts had begun without us! (Collections were still occurring, we just weren’t the ones carrying them out.) With a retrieval of thirty larvae the first day, a few hundred the next, as the week went on and the water warmed, by the time we were back on our 2am coffee-dependent work schedule, our catch had skyrocketed. This Monday marked our first day back on night work, and our haul had us bringing in ten thousand suckers by morning!

View from the bike path that takes us to work, Klamath Falls’ lifeline is the intricate network of waterways that seem to flow trough the town.