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ATLANTIC SALMON IN NORWEGIAN RIVERS- CHALLENGES AND OPPORTUNITIES Morten Stickler, PhD Environmental Advisor- Corporate CR&HSE staff Environmental coordinator- Innovation Department

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ATLANTIC SALMON IN NORWEGIAN RIVERS-CHALLENGES AND OPPORTUNITIES Morten Stickler, PhD

Environmental Advisor- Corporate CR&HSE staff

Environmental coordinator- Innovation Department

Statkraft at glance

Peru

271 MW

Chile

157 MW

Turkey

20 MW

Nepal 34 MW

Philippines

293 MW

Brazil

137 MW

Panama

(project)

Zambia

11 MW

Norway

11 442 MW Sweden

1 516 MW Finland

66 MW

UK

272 MW

Sri Lanka

2 MW

Laos 100 MW

Germany

2 670 MW

India

136 MW

Installed capacity*

17 000 MW Power production (2012)*

60 TWh

90% renewable energy

3 600 employees

AGUA IMARA

SN POWER

STATKRAFT

* Includes: Share in subsidiaries where Statkraft is majority owner 100 % of SN Power and Agua Imara’s installed capacity

3

Illustration: M. Stickler

“You cannot step twice into the same stream…” (Heraclitus, quoted by Platon in Cratylus)

Status Norway: Atlantic salmon Salmo salar L.

Increased numbers of multi sea winter salmon (3-7 kg and >7 kg) in 2011-2012 on the south-west coast of Norway probably due to improved marine conditions.

Total return of salmon 50% compared to 1983 level- mostly due to low level of salmon <3kg.

Increasing population in South-Norway and significant decrease in West-Norway.

Industrial and recreational fishing not a significant threat, except in Tana.

Two most important threats: Escape from fish farms and sea lice.

4

Thorstad & Forset, May 2013

Holistic and adaptive management

The national gene bank for salmon

established by the Directorate for Nature

Management in 1986 due to the difficult

situation for Norwegian wild salmon in many

rivers.

Statkraft has 2 gene bank and 8 hatcheries

(2 presmolt, 5 smolt, 1 for eggstocking).

Genebanks: Preserve genes, e.g. after

rotenon treatment of gyro infected rivers.

Restocking of wild fish less successful due to

low survival and low rate of returns (0.5-1%).

Internal new (2014) R&D program to evaluate

effect of restocking in rivers and reservoirs.

Targeting no restocking and focusing on sustainable populations of Atlantic salmon

6

How much water is needed….?

7

Flow

Environment

Is more better….?

How much water is needed….?

8

Flow

Environment

A carrying capacity vs flow level….?

How much water is needed….?

9

Flow

Environment

Seasonal requirements….? Holistic view…?

egg survival,

winter habitat

Sm

olt m

igra

tion

fry dis-

place-

ment? Spawning

Main

tain

geom

orp

holo

gy

Attra

ct

spaw

ners

Habitat

July

Our key challenges hydropower and salmon in Norway

10

1. Migration barrier and loss of connectivity

2. Spawning success and growth of juveniles

1. Migration barrier and loss of connectivity: Case Nidelva, South-East Norway

Challenges:

Weirs from 70’s build for estethic and

recreational reasons

Still water/low flow velocity, pike

Sedimented and silted areas

Limited population of salmon

Qmin: 3 and 15 cms

11

Weirs

Migration barrier and loss of connectivity:

Case Nidelva, south-East Norway

Solutions:

Hydraulic modeling to analyze removal

of weirs testing different scenarios and

outcomes

Removal of weirs

Biological monitoring of spawning and

juvenile densities of Atlantic salmon

before (since 2002) and after (2007) to

evaluate results

12

Removal of weirs, before - after

Spawning areas before-after removal of weirs

Fjeldstad et al., 2012

Densities of juvenile Atlantic salmon before-after

2

0

10

20

30

40

50

2003 2004 2005 2006 2007 2008 2009

Num

ber

of

fish

pr.

100 m

.

Year

Reference area

Restored habitat area 1

Restored habitat area 2

Fjeldstad et al., 2012

Our key challenges hydropower and salmon in Norway

16

1. Migration barrier and loss of connectivity

2. Spawning success and growth of juveniles

2. Successful spawning and survival of eggs and juveniles

Case Bjoreio and spawning- North-West Norway

Challenges:

Critical low level of Atlantic salmon population.

High level (>20%) of escaped farmed salmon

New action plan and investigations replaced

mandatory restocking in the river.

Hydro-regulation and low winter flow causing

drying and freezing of spawning areas and

eggs of Atlantic salmon

Lower water temperature during the first

feeding period (June/July) reduce fish growth

and increase mortality the following winter

17

Spawning in Atumn Winter time conditions

Winter flow and stranding of spawning areas

How much water to have 100% egg survival?

0

10

20

30

40

50

60

70

80

90

100

-50 0 50 100 150 200

Surv

ival (%

)

Water depth (cm)

Aure

Laks

Ukjent

Trout

Salmon

20

Correlation between water level during spawning period and proportion stranded redds

Water Depth last week October (m) # Sp

awn

ing

nes

ts in

str

and

ing

risk

are

as (

%)

21

Mapped needed discharge to obtain zero stranding of spawning redds.

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

0 0.5 1 1.5 2

Vannføring (m3/s)

Ande

l str

ande

te g

yteg

rope

r (%

)2004

2005

2006

2007

2008

2009

2010

2011

Gj.sn.

Discharge (cms)

# st

ran

ded

sp

awn

ing

red

ds

(%)

Spatial distribution of spawning areas is vital to increase total production of salmon.

1069 spawning areas registered

and analyzed 2004-2012.

Strong correlations between

river scale juvenile density

and the percentage river area

suitable for spawning

and the spatial distribution of

spawning areas.

Salmon

2

0

5

10

15

20

25

30

1999 00 01 02 03 04 05 06 07 2008

Nu

mb

ero

ffi

shp

r. 1

00

m .

0+

> 0+

Increased juvenile growth and density by altered water temperature

Modelled growth of juvenile salmon vs

water temperature

Replaced 40% of the cold water with

2-4 degrees warmer water by

releasing water from two other intakes

during summer.

Measured growth and densities of 0+,

1+ and 2+

Increased growth and densities as a

direct result of altered temperature in

the minimum release

23

Temperature on anadromous part of Bjoreio

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

1. jan. 1. mar. 1. mai. 1. jul. 1. sep. 1. nov.

Tem

pera

ture

(˚C

)

Before water manipulation (1988-91)

After water manipulation (2003-06)

By small modifications of the flow

regime a win-win situation is created by

improved environmental conditions for

salmon with limited level of production

loss

But it takes time, and data before-after

is critical, i.e. holistic and adaptive

management and crossdisciplinary

planning is crucial

Foto: LFI-Unifob v/B. Barlaup

Overall positive outcomes

Future..?

25

Handbook on hydropower and environmental design finalized Sept-2013

Focus species: Atlantic salmon (S.salar L.)

Up to date knowledge on hydropower and

Atlantic salmon- Environmental Design

Two main parts

1. Diagnosis

2. Solutions

Multidisciplinary linking biology and

hydrology

26

27

19 countries

35 key note speakers

230 young professionals

Total investment appr. : 210 000 Euro’s

Appr 1000 per reviewed papers

9 Global meetings

www.nowpas.eu

www.statkraft.com

THANK YOU