The increasing numbers of bank anglers and powerboats on the Kenai River may be damaging the river habitat.
The Alaska Department of Fish & Game released two long-delayed reports in October addressing the effect of bank angling and powerboat use on bank erosion in the Kenai River. The reports, covering the years 2000 and 2001, found that as more anglers fished the river, the more banks crumbled and vegetation disappeared.
The reports are the final two installments of a series commissioned by the Board of Fisheries in 1996 to study the effects of increased sport fishing participation on the Kenai River after the board increased the sockeye salmon escapement goal.
Sport fishing participation more than tripled on the Kenai River between 1977 and 1995. The Board of Fisheries requested that the ADF&G monitor angler use and impacts to the habitats on the river, which was done from 1997 to 2001.
Although the reports from 1997, 1998 and 1999 were published within two or three years, the reports from 2000 and 2001 never appeared.
At first, the research team encountered some snarls with methodology, said Mary King, a former fisheries biologist who served as the principal investigator for the study. When they began in 1997, there was no definitive methodology for studying bank change over time. By 1998, they had determined how to approach the measurements and were getting observable results by 1999.
“The reports that were published in ‘97 and ‘98, we were stumbling around trying to find a method that the Board of Fisheries asked us to do,” King said. “Once we found a method and were getting results, they never got published.”
The researchers focused on the herbaceous lands and shrublands to study angler effect because they would be more sensitive to foot traffic, said Patricia Hansen, King’s co-author on the study. They also tried to select an even number of sites on both sides of the river, she said.
“For each macrohabitat type, sites were selected as randomly as possible allowing for various levels of angler use,” Hansen wrote in an email. “We also checked to be sure both bank and meander were represented within each habitat type.”
The plant habitat on the banks was significantly impacted because of trampling by anglers, according to the 2001 report. As vegetation was trampled, bare ground and water cover increased. Invasive species moved into the damaged soil — dandelions, grass and horsetails. Low angler effort areas had a small increase and areas with many anglers saw less grass but more horsetails and dandelions.
About half the sites showed bank gain while the other half showed bank loss. Bank gain largely occurs when the bank has broken but not separated yet in a process called calving. The average bank loss came out to about .28 meters, slightly more than 10 inches, King said.
Some of the accelerated erosion underneath the edge of the bank can be attributed to the wake from powerboats and some is due to the increased presence of sport anglers, she said.
“What the conclusions indicated was that there are measurable changes in habitat that can be attributed to the presence of sport fishing on the Kenai River,” King said. “If you compound (powerboats) with whatever shore angling is going on, we saw changes in vegetation that were damaging to the natural habitat.”
STUCK IN DRAFT
That significant changes were detected over only three seasons was “cause for concern,” the researchers wrote in the conclusion. They recommended the fisheries managers reevaluate how sport fisheries are prosecuted on the Kenai River to minimize damage to the riparian habitats.
Though the results were presented to the Board of Fisheries in 2002, the studies were never published. King said she did not want to speculate as to why they were not published, but said the results had been filed on time and presented as requested.
In her presentation to the board in 2002, King made three recommendations: to continue assessment of shore angler use and bank position change until better methods are developed, to finish the aerial photogrammetry feasibility study and make recommendations for future application river-wide and to develop better programs to educate anglers on how to preserve the environment.
The second two were carried through, but the shore angler and bank change assessments were abandoned.
Jim Hasbrouck, the chief fisheries scientist for the Fish & Game in Anchorage, said the reports were delayed because of staffing changes. The reports were classified as “draft” for that time period.
“The information was presented to the Board of Fisheries, but several staffing changes happened at the time, people moving around into different positions,” Hasbrouck said.
During the 14 years it took to release the reports, several people called for their release at Board of Fisheries meetings, but the logs held at the Alaska Department of Fish and Game commissioner’s Office have no record of anyone ever submitting a public records request for the reports, said Lisa Evans, assistant director of Fish and Game’s Division of Sport Fish. There are also no records of correspondence about the reports between 2000 and the present between staff at the Soldotna Fish & Game office and the Commissioner’s office, Evans wrote in an email.
In a public comment submitted at the 2008 meeting, Gary Hollier of the Kenai Peninsula Fisherman’s Association cited King’s presentation in 2002 on the damage to the riverbanks and asked why there were no updated habitat reports in the years since. Two other members of the public also asked why there had been no updates on the habitat reports in 2008.
In 2014, Lisa Gabriel, also of the Kenai Peninsula Fisherman’s Association, submitted a public comment to the Board of Fisheries detailing that she knew the reports existed and asking why they hadn’t been published.
Gabriel said she never submitted a formal records request for the 2000 and 2001 reports because she was able to find the draft versions on the Internet. When she requested a copy of the most current habitat report, she was given another Kenai River habitat assessment from 2010 from a team of researchers from Inter-fluve, a river restoration research firm, and Cramer Fish Sciences, a fisheries research firm. The report had been presented to Fish & Game and to the Kenai River Sportfishing Association. It primarily focused on restoration efforts, but in the section addressing bank erosion said some reports had indicated that increased angler traffic caused bank loss. The report concluded that there is insufficient information about the scale of habitat changes and what causes them.
“There was nothing on biological habitat information,” Gabriel said. “(The report said) we’re repairing walkways, that sort of thing. All of the reports we were seeing at the Board of Fish level, none of them were official reports.”
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