kudos to a colleague

this is in two days for anyone in the sacramento area!

If you want to hear Joe Merz being interviewed on public radio, there will be a live interview on Insight, Capital Public Radio’s daily talk program, at 2:40 p.m. Thu 8/10/2006.


| http://www.capradio.org/insight


University of California, Davis
August 4, 2006

CALIFORNIA WINE: COMPLEX AND SMOOTH WITH HINTS OF SALMON

[Editor's note: High-resolution, color photos are available by e-mail.
They show vineyards, rivers, grapes and animals scavenging fish
carcasses. Contact Sylvia Wright, below.]

What does it take to make a fine California wine? Grapes, water,
sunshine, the skilled hand of a master vintner -- and a few thousand
dead fish.

A few thousand dead chinook salmon, that is, according to new research
that shows for the first time that the salmon that die naturally in
California's Mokelumne and Calaveras rivers contribute significantly to
the growth -- and likely the quality -- of wine grapes raised nearby.
How? Wild animals eat the salmon carcasses, converting the
nutrient-laden fish into fertilizer for the grapevines.

The study was led by Joseph Merz, a Lodi-based fisheries biologist with
East Bay Municipal Utility District and an instructor at Sacramento
State University. Merz's research collaborator was his former Ph.D.
adviser and the leading authority on California native fishes, Peter
Moyle of UC Davis -- which also happens to be the world's premier wine
school.

Using a combination of their own new studies and other researchers'
earlier findings, Merz and Moyle examined what happens after chinook
salmon incorporate the rich chemistry of the northern Pacific Ocean
(carbon, nitrogen, phosphorus and more) into their body tissues, then
carry it upstream in fall and winter to their inland California spawning
grounds.

By tracing the movement of elemental "fingerprints" called nitrogen
isotopes, the scientists found that when the salmon die upstream after
spawning, natural scavengers move the marine-origin nutrients into the
terrestrial food chain -- either through their wastes or by dropping
fish carcasses onshore.

Merz and Moyle recorded 14 species of animals feeding on salmon
carcasses, including turkey vultures, raccoons, river otters, rats,
coyotes and even deer.

Before long, the nutrients travel through soil and water into wine
grapes being grown commercially along the riverbanks.

"What we found is that the grapes close to the river get up to 25
percent of their nitrogen from salmon," Merz said. "In wine making,
nitrogen affects yeast growth and sugar fermentation. No doubt some of
the best California wine has salmon in it."

While their results should enliven the table talk over dinners of wild
salmon and pinot noir, Merz and Moyle say there's more to it.

"Our study indicates that managing regulated rivers for salmon has
benefits far beyond simply providing fish for fishermen," they write.
"The marine-derived nutrients of salmon can positively affect both
natural riparian systems and agricultural crops, with considerable
economic benefit."

For starters, grapes getting one quarter of their nitrogen from natural
sources, rather than from commercial fertilizers, is good for the
environment and for the farmer's bottom line: In the Central Valley
region where the study was done, nitrogen fertilizer costs $500 to
$2,800 per ton. That does not include labor and fuel costs of applying
the fertilizer -- services performed gratis in this instance by
wildlife.

In an interesting aside, the scientists noted that the operators of
state-run salmon hatcheries, after they harvest eggs and milt from
spawning fish, routinely dispose of the carcasses rather than placing
them back in the river. "Hatcheries consequently could be removing
significant amounts of nitrogen of value both to agriculture and to the
local ecosystems," Moyle said.

The study, "Salmon, Wildlife, and Wine: Marine-Derived Nutrients in
Human-Dominated Ecosystems of Central California," is published in the
June 2006 issue of the journal Ecological Applications and was noted in
the news pages of the July 21 issue of the journal Science.

The research was funded by the East Bay Municipal Utility District,
through its financial support of Merz's doctoral study of using gravel
enhancement to restore salmon spawning in the Lower Mokelumne River.

The researchers thanked the East Bay Municipal Utility District's
Fisheries and Wildlife Office for help with monitoring; Woodbridge
Irrigation District for access to monitoring facilities; the California
Department of Fish and Game for spawning data and salmon carcasses; and
several local wine grape producers for access to vineyards.

Media contact(s):
* Joseph Merz, East Bay Municipal Utility District, (209) 365-1093,
jmerz@ebmud.com
* Peter Moyle, UC Davis Wildlife, Fish and Conservation Biology,
(530) 752-6355, pbmoyle@ucdavis.edu (Moyle is best reached by e-mail.)
* Sylvia Wright, UC Davis News Service, (530) 752-7704,
swright@ucdavis.edu