Se Identifica Presencia de Alga Invasora Didymo en Rio Futaleufu. (USGS findings confirmed)

Este viernes se reunieron investigadores expertos en Turismo Sustentable y Biólogos del Centro de Investigación en Ecosistemas de la Patagonia (CIEP), con autoridades regionales y operadores de Pesca con Mosca para analizar la situación.

En dependencias del CIEP se reunieron científicos con el SEREMI de Economía, Fernando Guzmán; el Director de la DIPLADE, Mark Buscaglia; el representante de la Subsecretaría de pesca, Manuel Martínez y operadores de pesca con mosca, para estudiar el problema y definir pasos a seguir, luego de encontrar esta alga denominada Didymosphenia sp, más conocida como “moco de roca”, un tipo de alga microscópica unicelular que habitan en ambientes acuáticos. En Chile, no se había detectado su presencia desde el año 1964. Esta microalga causa preocupación porque altera gravemente el ecosistema acuático.

Fabien Bourlón, Coordinador del Departamento de Turismo Sustentable del CIEP, cuenta que supieron de la existencia de esta alga en la región, gracias al aviso de Marcel Sijnesael, operador de Pesca con Mosca de La Junta, quien se puso en contacto con ellos con la alarmante noticia. “Creo que el sector turismo tiene que evaluar la situación y conjuntamente con los científicos y las autoridades responsables (SAG y SERNAPESCA) debe generarse un plan de contingencia antes del inicio de la próxima temporada, cuando se reanuden las actividades recreativas en los ríos y aumenten los riesgos de difusión de esta alga”, señaló en científico.

Por su parte, el Director Científico del CIEP, Giovanni Daneri, señaló que “se analizaron las muestras de agua provenientes del río Espolón, Futaleufú, Chile; y los resultados confirman la presencia de abundante número de diatomeas pertenecientes al género Didymosphenia sp (moco de roca). Por otra parte, los resultados del análisis de la masa de material fresco encontrada en el área de muestreo, indican que esta densa capa de mucílagos proviene también del frustulo (dióxido de silicio hidratado) de la diatomea Didymosphenia sp.”.

Mas aqui: http://www.vientopatagon.cl/main/?p=17581 & http://www.ciep.cl/index.php?cont=noti&id=65

US Geological Survey Confirms Didymo in Chile, Region X (Chiloe District)

Technical Announcement:

[USGS FORT] Didymo Confirmed in Remote Chilean Rivers

The presence of the invasive diatom Didymosphenia geminata, or didymo, has been confirmed in remote Chilean rivers near Esquel, Argentina, by a U.S. Geological Survey scientist and diatom expert.

Didymo is an aquatic invasive species in several regions of the world. It invaded New Zealand in 2004 and has since spread to 32 watersheds there. The species is problematic because of its propensity to erupt into massive “nuisance blooms” that cover stream and river bottoms. These dense masses substantially alter the aquatic habitat for other life forms, such as invertebrates and fish, and consequently the health of the aquatic ecosystem.

Although the presence of didymo was reported in Lago Sarmiento, Chile, in 1964, this is the first known occurrence of a nuisance bloom in South America. The newly discovered bloom was reported on Rio Espolon and Rio Futaleufú, covering a total of more than 56 river kilometers.

Didymo is known to survive in damp conditions for more than 30 days and can be transported on the gear of aquatic recreationists. The pristine, low-nutrient rivers that recreationists seek are the same ones that are most vulnerable to large blooms of didymo, if the species is introduced.

Didymosphenia geminata cells produce large amounts of mucilaginous stalks. These stalks are white and look like wet toilet paper when clinging to fishing line. The stalks, cells, and associated sediment can resemble raw sewage lining riverbeds or streambeds.

Didymo presents a paradox to scientists because it is able to create large amounts of biomass in low-nutrient rivers. Recent work indicates that the amount of stalk produced is related to the phosphorus concentration of the water, implying that the stalk acts to attract and take up phosphorus for the cells. In some regions of the world, the blooms are persistent for a number of years after the initial invasion.

Sarah A. Spaulding
U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192

More here: http://www.usgs.gov/newsroom/article.asp?ID=2491

Didymo Distribution Map - May 2010

[ Enlarge Image ]

Didymosphenia has been spotted along 7 kilometers of the Rio Espolon and 49 Kilometers of the Rio Futaleufu. (56 kilometers total)

The limit of the infection appears to be the Rio Espolon & Rio Futaleufu confluence. The Futaleufu River coming from Argentina appears clean. The Rio Azul appears clean. Didymo "stalk material" can be found along most of the Rio Futaleufu, at the high water marks, and almost as far as Lago Yelcho.

Slides of the Rio Espolon Samples Identified as Didymosphenia geminata by USGS

Image of the silica cell wall of the diatom 'Didymosphenia geminata' from Rio Espolon, Futaleufu, Region X, Chile. The sample was collected in April 2010 from an extensive bloom on the river. The image has been processed to show the silica cell wall, removing the organic cell contents and the stalk material. (Image by Sarah A. Spaulding, US Geological Survey, FORT). Enlarged: here.

Didymosphenia on the Rio Espolon, Chile - Video

This video was taken on the Rio Espolon, adjacent to the village of Futaleufu on April 20, 2010:

Didymosphenia on the Rio Espolon, Chile - Photo Slideshow

These photos were taken on the Rio Espolon, adjacent to the Village of Futaleufu on April 19, 2010:

Chile Government was warned about the Didymo threat in 2007

In a United States Government Environmental Protection Agency White Paper the governments of Australia, Argentina, Chile & Peru were warned about the potential threat of Didymosphenia geminta to their waterways:

"Rivers in the southern hemisphere are particularly at risk to new introduction and invasion. Appropriate agency personnel in Australia, Argentina, Chile and Peru should be notified and made aware of the potential ecological damage and urgency of implementing decontamination procedures." (page 11)

http://www.epa.gov/region8/water/didymosphenia/White%20Paper%20Jan%202007.pdf

FIGURE: Map of the world showing regions where suitable stream habitats for D. geminata are located. (Map by Kris McNyset, US Environmental Protection Agency).

The government of Australia took the 2007 warning seriously and prevents Didymo infected items from entering the country:

What are the risk items?

Didymo can survive in damp moist conditions and is often inadvertently carried in sporting equipment and fabrics such as:

fishing equipment: rods, reels, bags, rope, nets, knee guards, gators, felt soled shoes, waders, recreational and watersport equipment: wetsuits, neoprene socks, waterskiing and wakeboarding equipment (including components) buoyancy vests, kayaks, canoes and other watercraft, paddles, spray decks, spray skirts, soft foam handles, hiking gear and swimwear.

What can you do before returning to Australia?

All travellers carrying such items need to thoroughly clean and completely dry all components, inside and out. It is also a good idea when you’re packing your bags to ensure all risk items can easily be accessed when required for inspection.

What to do when arriving in Australia?

It is important that you:

Declare all items on your Incoming Passenger Card

Present all items to an AQIS Officer for inspection.

What happens next?

The AQIS Officer will inspect all items to assess the level of risk each item presents. Once assessed, the AQIS Officer will advise you whether or not the item needs to be treated before it can enter Australia. If it requires treatment, it will be treated in the nearest AQIS approved treatment facility, subject to availability; which may result in delays in getting items back. If the risk item can not be treated it will need to either be destroyed or re-exported. All treatment, destruction or re-exportation costs are at the owner’s expense.

More here: http://www.daff.gov.au/aqis/travel/entering-australia/didymo/didymo2

Australia border control video here: http://www.youtube.com/watch?v=8xxWI2WGxyY

Currently, Australia & Tasmania remain free of Didymosphenia geminata.

BioSecurity New Zealand Estimates Economic Impact of Didymosphenia Invasion

This assessment estimates potential present value impacts of didymo on New Zealand’s commercial eel fisheries, municipal, industrial and agricultural water intakes, community, municipal and domestic drinking water, local recreation values, international and domestic tourism expenditure, local and national existence values and existence values associated with extinction of native species, over the eight years 2004/05 to 2011/12, to total:

$57.798 million under the low impact scenario;

$167.233 million under the medium impact scenario; and

$285.132 million under the high impact scenario.

Weighting the three scenarios by their relative probabilities suggests expected present value total impacts over this period of $157.599 million.

Total impacts are dominated by reduced recreation values, loss of existence values associated with extinction of native species and reduced tourism expenditure, followed by increased costs for water intakes and reduced local and national existence values. Total impacts are greatest in the North Island and central South Island. Although the lower South Island has the largest amount of highest risk environment for survival of didymo and is where impacts occur earliest, the central South Island and North Island have substantially larger human populations to suffer reduced recreation and existence values.

Sensitivity analysis

Without the loss of native species, present value total impacts over the period 2004/05 to 2011/12 would be reduced to between $39.525 million and $230.312 million.

A two year delay to the arrival of didymo in the North Island would reduce the present value total impacts incurred over the longer period 2004/05 to 2013/14 by between $5.024 million and $62.419 million (9 and 22 per cent). Slowing the spread of didymo through each region (from five to seven years) would reduce the present value total impacts incurred over the longer period 2004/05 to 2013/14 by between $26.302 million and $142.748 million (46 and 50 per cent)

More here: http://www.biosecurity.govt.nz/pests-diseases/plants/didymo/economic-impact.htm

Didymosphenia Bloom on the Rio Espolon - May 2010

Chilean Lodges take innovative step in combatting spread of aquatic pests

The Patagonian BaseCamp Lodge and The Temple Camp have purchased safe wading boots for the use of all their guests from Korkers in the USA. No need to travel with bulky boots is a bonus!

It seems we are hit at every turn these days with alarming news about some new aquatic threat to our favorite streams and rivers. New Zealand mud snails, didymo, whirling disease…the onslaught seems relentless, and the potential for destruction dire. We are told repeatedly that the only practical method to control the spread of these invaders into our waters is prevention. Simply stated, if you must wear waders and wading shoes from potentially contaminated fisheries into non-affected waters, rather extreme cleaning techniques are mandatory. Especially dangerous are felt-soled wading boots, as the porous soles provide convenient nooks and crannies in which these offenders can hide, and even live in for extended periods of time. Those still-damp boots in your garage from a fishing trip last week may harbor live threats, ready and waiting to explode into a new and susceptible environment. One need look no further than some of the great New Zealand trout streams which have been devastated by didymo, to comprehend the damage possible in such a pristine and prized angler destination as Patagonia.

( Read More Here )