Friday, May 26, 2017

Siberian Taimen: Ensuring the Survival of the River Wolf, by Spencer Bell

Deep in the most remote regions of Russia, China, and Mongolia lurks the largest salmonid in the world, the Siberian Taimen. Sitting at the crossroads of folklore and reality, the Hucho taimen has long held the imagination of western anglers searching for the thrill of fighting “the big one”. Due to the life history of Taimen though, angling must be done responsibly to avoid negative impacts. Even the removal of a single reproducing Taimen could have devastating impacts. How then can we ensure the continuation of fish such as the Siberian Taimen in a world developing in ways that may harm them? Historically, low population densities of the Siberian Taimen were found throughout Russia and the northern watersheds of China, Kazakhstan, and Mongolia (Dulmaa 1999; Vander Zanden et al. 2007; Hogan and Jensen 2013).

Taimen thrive in swift flowing water with high oxygen levels.  Depending on competition, they can require up to 60 river miles for home range.  Although not anadromous, Taimen travel huge distances during spawning periods.   After spawning, females place 4,000-30,000 eggs under gravel in stream bottoms (Hogan and Jensen 2013).  As Taimen are both slow growing and late to mature, it takes five to seven years to reach sexual maturity.  Those few Taimen that reach maturity can grow as large as 60 inches and 60 pounds over a 50 year lifespan, though individuals of that age are rare due to targeted fishing (Holcik et al. 1988).  As opportunistic feeders, Taimen live by the rule that if it fits in their mouth, its food.  This includes mostly fish, but also birds, rodents, bats, and even other Taimen if alternative food sources are unavailable.  Large fish live alone, but younger fish will travel and even hunt in packs at times lending this fish the moniker, the river wolf. 
Siberian Taimen, Hucho taimen.  Source 
Before access to Taimen fisheries was opened to the west, the only glimpse anglers had of the river wolf was through the lens of myth.  Russians told of fish 30 feet long, able to rip trees holding set lines out of the ground.  In Mongolia, stories told of a giant Taimen stuck in ice.  Nomads ate of the fish chunk by chunk until the spring thaw.  Once the giant Taimen was free, it climbed onto land and devoured the nomads in return.  Myths such as these have contributed to local aversions of streams where Taimen are found.  In addition to rarely eating fish, Mongolians are careful when allowing children and livestock in streams home to Taimen.  In Buddhist culture though, Taimen as the children of river spirits.     Hucho taimen may be known to the Chinese as "the river god's daughter,"     Mongolian Buddhist have protected the home streams of Taimen for generations in reverence of their beliefs for centuries.  But even this cultural affinity has not been able to protect Taimen from recent development along their native streams. 
Three Taimen, underwater photo from Eg River, northern Mongolia.  Source. 
Due to its ecology, Siberian Taimen are especially vulnerable to impacts that remove individuals from the breeding population.  In Russia, historical commercial and subsistence fishing is believed to have been as high as 150-200 metric tons annually.  By the mid-1950s mass poaching combined with contamination from industry and agricultural waste had led to localized extinctions throughout the country.  Even when protections were put in place in 1988, continued illegal harvesting reduced populations to the point that fish may have been unable to find mates in coastal areas of northern Lake Baikal.  In China where Taimen are limited to two watersheds, illegal fishing and overharvest have led to population declines as high as 95% with ranges limited to 7% of historic ranges in the past 50 years (Ocock et al. 2006).  With native populations plummeting, illegal fish trade has developed between China and Mongolia resulting in further declines where the Taimen is not as heavily harvested (Chandra et al. 2005).  Outside of this illegal trade, impacts on Taimen in Mongolia are mainly due to development, mining, and overgrazing.  As fishing is not historically part of Mongolian culture, population declines have been more moderate at approximately 50% in the past 30 years.  These declines are predicted to increase in the future though due to illegal trade with China (Chandra et al. 2005).  In Mongolia, hope for the Taimen’s survival may rest in the nation’s ability to develop economic incentives to limit over harvest.

Although declining on all fronts, the future of the Taimen may actually depend on fishing itself (Stubblefield et al. 2005; Vander Zanden et al. 2007).  With the cooling of Cold War tensions in the late 1980s-early 1990s, western anglers first gained access to the streams where Taimen were native.  In Mongolia, a new tourist industry began to be developed to cater to the needs fishermen.  Instead of targeting these fish for filets as the locals though, these anglers were looking to catch “the big one” for bragging rights then release their prize.  Nearly as soon as the iron curtain fell, outfits began popping up that focused on transporting fly fishermen to the most remote areas of Siberia to battle this fish.  Especially in Mongolia, recreational fishing has offered an economic alternative to poaching that protects Taimen in areas with little other development.  To ensure the health of recreational fisheries, anglers began directing funds to the conservation of Taimen and the streams they inhabit.  This has led to the establishment educational initiatives targeting Taimen conservation in Mongolia and the establishment of nearly 500 river miles of conservation land where only catch and release fly fishing is allowed (Bailey 2012; Adachi).  To promote local compliance with these efforts, conservationist have collaborated with Buddhist monks to ensure that both the Taimen and the streams it inhabits are protected in a culturally sensitive manner.

Are these conservation efforts enough to save the Siberian Taimen?  "This fish is not like other trout and salmon species," said Zeb Hogan, a fisheries biologist with the University of Reno in Nevada.  By bringing locals into the picture and offering them alternatives to development, pressures on local fisheries have been lessened.  In Mongolia this methodology is being followed through using catch and release fly fishing as an engine of low impact development that avoids overharvesting Siberian Taimen.  The efforts in Mongolia combining a local cultural affinity for streams, anglers actively invested in the persistence of their aquatic foe, and economic development that creates an alternative to activities that harm Taimen populations serves as a guide to effectively conserve endangered fisheries.  If similar efforts can be implemented throughout its range, the Siberian Taimen may rebound from the declines it currently faces.

References 

Adachi, Satoshi. “The Pacific’s Largest and Most Ancient Salmon Species.” WildSalmonCenter.com. 
Bailey, D. H. 2012.  Collaborative conservation of Taimen (Hucho taimen) through education and awareness Khovsgol Aimag Mongolia.  ScholarWorks at University of Montana.
Chandra, S., D. Gilroy, S. Purevdorj, and M. Erdenebat. 2005. The feeding behaviour of fish from the upper Lake Baikal watershed of the Eroo River in Mongolia. Mongolian J. Biol. Sci. 3(1): 39–45.
Dulmaa, A. 1999: Fish and fisheries in Mongolia. No. 385. Rome: FAO.
Hogan, Z., O. Jensen. 2013: Hucho taimen. The IUCN Red List of Threatened Species 2013 e.T188631A22605180. DOI: 10.2305/IUCN.UK.2013–1.RLTS.T188631A22605180.en.
Holcik, J., K. Hensel, J. Nieslanik, and L. Skacel. 1988. The Eurasian huchen, Hucho hucho, largest salmon of the world. Kluwer Academic Publishers, Boston, Mass.
Ocock, J., G. Baasanjav, J. E. M. Baillie, M. Erbenebat, et al. 2006: Mongolian Red List of Fishes – Regional Red List Series. Zoological Society of London, London, vol. 3
Stubblefield, A., S. Chandra, S. Eagan, D. Tuvshinjargal, G. Davaadorzh, D. Gilroy, J. Sampson, J. Thorne, B. C. Allen, and Z. Hogan. 2005. Impacts of gold mining and land use alterations on the water quality of central Mongolian rivers. Integr. Environ. Assess. Manag. 1(4): 365–373.
Vander Zanden, M.J., L. N. Joppa, B. C. Allen, S. Chandra, D. Gilroy, Z. Hogan, J. T. Maxted, and J. Zhu. 2007. Modeling spawning dates of Hucho taimen in Mongolia to establish fishery management zones. Ecol. Appl. 17(8): 2281–2289.

2 comments:

  1. Great write up. Small note: it's the University of Nevada - Reno.

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