Mat-Su Basin - Biological Value - Mat

Anadromous Proportion
in Watershed
Alaska Department of Fish and Game
maintains a Catalog of Waters Important for the
Spawning, Rearing or Migration of
Anadromous Fishes that documents spawning,
rearing, and presence of anadromous fish.
Inclusion in the catalog affords certain state
protections under the Anadromous Fish Act
(AS 16.05.871).
Documenting anadromous waters in Alaska is
complicated by remoteness, short field seasons,
and limited resources to conduct inventories.
Surveys may not capture lifestage information
due to varying timing of return of spawning
adults of different species and seasonal
movement of rearing juveniles. For spawning,
the data may reflect Chinook and sockeye
salmon better than the other species.
% Anadromous
highest
lowest
for each watershed:
miles of anadromous
waters divided by
stream length
S u si tn a
Currently the catalog contains less than 5000
miles of the more than 23,900 miles of mapped
streams in the Mat-Su Basin. Despite
providing an incomplete record of salmon
habitat, the catalog can be used to identify
patterns of spawning and rearing habitat across
the Mat-Su Basin.
p
a/ K
Ka s
hw it n a
a
tn a
c
Tala
n
Ye
Wi l l o w
litna
hu
L it
tl e
S
a
us i t n
Chijuk Creek
Subwatershed - 75 mi.
All anadromous waters which are coded as spawning and/or rearing were merged for all
salmon species and then intersected with the watersheds. Stream lengths have been summed
by watershed. The data used for this map will be updated over time as we learn more about
Mat-Su salmon and their habitat, which could result in changes to this map in the future.
Interpretation of this data is most appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
Watersheds with Most
Documented Miles of
Spawning & Rearing
ro t o
iltn
na
Lake Creek Mouth
Subwatershed - 56 mi.
e tna
The National Hydrology Dataset aims to map
all national waterbodies. Like the Anadromous
Waters Catalog, however, it is not complete yet
for the Mat-Su Basin. It does provide a way to
assess the relative amount of salmon habitat for
all the waterbodies in a watershed.
Sh
hk
K ah
en t
lke
ee
es
ke
D
La
Sk w
Ta
C h ul i t n a
Peters Creek
(S. Kahiltna River)
Subwatershed - 61 mi.
Cook
Inlet
South Kroto Creek
Subwatershed - 59 mi.
ta
Ma
a
nu sk
Watershed
Miles
Mat-Su Basin - Biological Value
Salmon Spawning and Rearing Length
Chijuk Creek
75
Peters Creek
(S. Kahiltna River)
61
South Kroto Creek
59
Lake Creek Mouth
56
Beaver Creek
(Kahiltna River)
48
37 - 75
Low er Little
Willow Creek
46
19 - 36
North Kroto Creek
46
Moose Creek
Mouth
45
Kroto Creek
Headw aters
45
Fish Creek
(Susitna River)
42
Major Streams
Total Length (Miles) of Documented
Spawning or Rearing Streams in Watershed
0
0
10
20
20
1 - 18
40
Miles
40
Kilometers
80
DATA SOURCES:
Alaska Dept. of Fish and Game - Anadromous Waters Catalog - 2008.
Alaska Geographic Data Committee (AGDC) Hydrography Subcommittee.
http://agdc.usgs.gov/hydro/ - United States Geological Survey (USGS)
Map 2
Alaska Department of Fish and Game maintains a
Catalog of Waters Important for the Spawning,
Rearing or Migration of Anadromous Fishes that
documents spawning, rearing, and presence of
anadromous fish and some resident fish.
Inclusion in the catalog affords certain state
protections under the Anadromous Fish Act (AS
16.05.871).
Anadromous Density
in Watershed
Documenting anadromous waters in Alaska is
complicated by remoteness, short field seasons,
and limited resources to conduct inventories.
Surveys may not capture lifestage information due
to varying timing of return of spawning adults of
different species and seasonal movement of
rearing juveniles. For spawning, the data may
reflect Chinook and sockeye salmon better than
the other species.
Anadromous
Density
highest
lowest
for each watershed:
miles of anadromous
waters divided by
watershed area
Currently the catalog contains less than 5000
miles of the more than 23,900 miles of mapped
streams in the Mat-Su Basin. Despite providing
an incomplete record of salmon habitat, the
catalog can be used to identify patterns of
spawning and rearing habitat across the Mat-Su
Basin.
lke
e t na
ee
es
ke
D
La
Sh
hk
Kas
hw itn a
a
roto
iltn
a/K
Ka h
The density of documented salmon use within a
watershed may indicate a watershed’s contribution
to maintaining healthy salmon populations in the
Mat-Su Basin. Due to the general lack of lifestage
information in the catalog, this assessment
mapped density of spawning and rearing and
density of all lifestages for comparison.
p
Ta
C h ul i t n a
S u s i tna
tan
Ma
tna
c
Tala
n
Ye
Wi l l ow
litna
hu
Li
i tn
Sus
e
l
t
t
a
u ska
Mat-Su Basin - Biological Value
Salmon Spawning and Rearing Density
Density of Documented Spawning & Rearing
in Watershed (Length per Watershed Area)
High
Low
0
All anadromous waters which are coded as spawning and/or rearing are merged for all
salmon species and then intersected with the watersheds. Streams lengths have been summed
by watershed and then divided by the watershed's area. The data used for this map will be
updated over time as we learn more about Mat-Su salmon and their habitat, which could
result in changes to this map in the future. Interpretation of this data is most appropriate at
the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
0
Cook
Inlet
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
Alaska Dept. of Fish and Game - Anadromous Waters Catalog - 2008.
Alaska Geographic Data Committee (AGDC) Hydrography Subcommittee.
http://agdc.usgs.gov/hydro/ - United States Geological Survey (USGS)
Map 3
King Salmon Distribution
All Lifestages
p
ee
o se
on
tan
Mo
es
ke
D
La
hk
King Salmon
Index Streams
Index Stream
Alexander Creek
Cache Creek
Chuijuk Creek
Chulitna River
Clear Creek
Deshka River
Goose Creek
Indian River
Kroto Creek
Lake Creek
Lewis River
Little Susitna River
ar
a
C le
Pr
ai
rie
C hu
li t n
a
The Susitna River supports the fourth
largest Chinook (king) salmon
(Oncorhynchus tshawytscha) run in Alaska.
Between 100,000 to 200,000 king salmon
return every year to the Susitna and its
tributaries. These large returns support
large and popular sport fisheries in the
Mat-Su Basin. Alaska Department of Fish
and Game count returning fish at the major
spawning areas. These 26 index streams,
mapped here, provide spawning habitat for
most returning Chinook salmon.
Sh
M
a /K
ro to
Wi ll o w
c
Tala
Ale
x an
litna
hu
der
King Salmon Index streams are intersected with the watersheds which are scored
1 for presence and 0 for absence of an index stream. A total of 26 index streams
are mapped within 82 watersheds and/or subwatershed units. The data used for
this map will be updated over time as we learn more about Mat-Su salmon and
their habitat, which could result in changes to this map in the future.
Interpretation of this data is most appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
Cook Inlet
Lit
tl
s it n
e Su
a
Little Willow Creek
Montana Creek
Moose Creek
Moose Creek Matanuska
North Fork
Kashwitna River
Peters Creek
Portage Creek
Prairie Creek
Sheep Creek
Sucker Creek
Talachulitna River
Trapper Creek
Willow Creek
Wolverine Creek
Chinook salmon generally spawn in deeper
flowing waters during late summer.
Juvenile Chinook salmon emerge from the
gravel as fry in the spring and spend one
year rearing in freshwater before migrating
to the ocean the following year. Chinook
salmon spend between one and five years
in the ocean before returning to spawn as
adults. Chinook salmon have been
documented in 2,815 river miles in the
Mat-Su Basin.
Mat-Su Basin - Biological Value
Chinook Salmon Spawning
Major Streams
King Salmon Index Stream - ADF&G
Watersheds with King Index Stream
Contains Index Stream
0
0
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
King Salmon Index Streams, Alaska Dept. of Fish and Game - Sport Fish
Division - 2008. Anadromous Waters Catalog, ADF&G; 2008.
Map 4
Coho salmon (Oncorhynchus kisutch) may
be the most widely distributed Pacific
salmon in the Mat-Su Basin. Coho salmon
generally spawn throughout many
headwaters during the fall.
Coho Salmon Distribution
All Lifestages
Juveniles can spend from one to three years
rearing in freshwater, the longest
freshwater residence of the salmon species,
making them possibly more vulnerable to
changes in freshwater habitats. They prefer
smaller tributary streams, backwater and
off-channel habitats, and beaver ponds.
Wetlands within a watershed also provide
juvenile coho salmon rearing habitat. Few
of those rearing wetlands are documented
in the Anadromous Waters Catalog, which
contains primarily lakes and streams.
Coho salmon in the Mat-Su Basin support
the area’s largest recreational harvest.
Commercial harvest of Mat-Su Basin coho
salmon occurs in Upper Cook Inlet in
mixed stock fisheries; it is unknown what
portion of those harvested fish were bound
for Mat-Su Basin streams.
es
ke
D
La
Sh
hk
p
a/K
na
ro to
Yen
t
ee
Mat-Su Basin - Biological Value
Coho Salmon Rearing
c
Tala
Major Streams
A le x a
litna
hu
Coho Salmon Rearing - ADF&G
Watersheds with Coho Salmon Rearing
nd er
documented rearing
0
The Alaska Department of Fish and Game codes all anadromous waters by species and
lifestage. This map highlights Coho salmon rearing stream segments. These streams are
intersected with the watersheds which are scored 1 for documented presence and 0 for
absence. A total of 147 watersheds contain documented coho rearing. The data used for this
map will be updated over time as we learn more about Mat-Su salmon and their habitat,
which could result in changes to this map in the future. Interpretation of this data is most
appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
0
Cook
Inlet
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
Alaska Dept. of Fish and Game - Anadromous Waters Catalog - 2008.
Map 5
Sockeye salmon (Oncorhynchus nerka) spawn
and rear in numerous lake and river systems in
the Mat-Su Basin. Most sockeye salmon
spawning occurs in lakes and their associated
tributary streams during late summer and fall.
Sockeye salmon spawning has been identified
in over 1845 river miles in the Mat-Su Basin.
At least seven major lakes in the Susitna River
drainage provide most of the known rearing
and spawning habitat for sockeye salmon
production.
Sockeye Salmon Distribution
All Lifestages
C hu
li tn
a
Although these lakes receive the majority of
spawners, significant contributions toward
overall productivity of Mat-Su sockeye salmon
comes from minor systems, which include
small lakes and streams as well as mainstem
and side channel spawning and rearing areas in
the Susitna River drainage, Knik Arm streams,
and the Knik and Matanuska rivers.
S u s i tn a
Byers
Lake
Stephan
Lake
Swan
Lake
Ta
Chelatana
Lake
Residents of the Mat-Su have expressed
concern about the health of sockeye salmon
stocks in the Mat-Su Basin. Both the Yentna
River and Fish Creek have not met escapement
goals in some recent years, and the Alaska
Board of Fisheries has identified the Susitna
River sockeye salmon stock as a Stock of Yield
Concern.
p
es
ee
D
ke
Sh
hk
a
roto
il t n
a/K
Kah
ta
Ma
Wi ll ow
n
Ye
hu
tna
c
Ta l a
litn a
Judd
Lake
et n a
Larson
Lake
La
Skwentna
Shell
Lake
Hewitt
Lake
lke
Cook Inlet Aquaculture Association studies
sockeye spawning lakes each year to improve
knowledge about sockeye salmon spawning
and habitat.
L it
t
usi
le S
n
u sk a
Mat-Su Basin - Biological Value
Sockeye Salmon Spawning
Cook Inlet Aquaculture Association
Sockeye Salmon Study Lakes
t na
Major Streams
Sockeye Salmon Spawning - ADF&G
Watersheds with Sockeye Salmon Spawning
documented spawning
0
The Alaska Department of Fish and Game codes all anadromous waters by species and lifestage. This map
highlights Sockeye salmon spawning stream segments. Additionally, the map depicts lakes where sockeye
salmon spawn which the Cook Inlet Aquaculture Association studies each year. 77 watersheds contain
documented sockeye salmon spawning. The data used for this map will be updated over time as we learn
more about Mat-Su salmon and their habitat, which could result in changes to this map in the future.
Interpretation of this data is most appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
Cook
Inlet
0
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
Alaska Dept. of Fish and Game - Anadromous Waters Catalog - 2008.
Cook Inlet Aquaculture Association - CIAA - important sockeye lakes.,
2008.
Map 6
Chum salmon (Oncorhynchus keta) spawn
on gravel bars and pool tail-outs in many
rivers and streams during late summer and
fall in the Mat- Su Basin. Juveniles spend
little time in freshwater after emerging from
the gravel in the spring before migrating to
the ocean. Chum salmon can spend
between one and five years maturing in the
ocean before returning as adults to spawn.
The Anadromous Waters Catalog,
maintained by the Alaska Department of
Fish and Game, documents chum salmon in
over 1140 river miles in the Mat-Su Basin.
Chum Salmon Distribution
All Lifestages
Little is known about the status of chum
salmon populations in the Mat-Su Basin,
although commercial harvests and
incidental escapement counts in recent
years seem to indicate that populations are
recovering from record low returns
attributable to severe fall flooding in 1986.
Chum salmon commercial harvests have
declined dramatically since 1986, and less
than 200,000 fish have been harvested in
most years from 1996 to 2004. Although
harvest levels for chum salmon have been
low in recent years, harvest in the
commercial fishery is affected by closures
and restrictions to protect sockeye salmon
stocks. Low prices have also reduced
fishing effort in recent years.
Ta
C h ul i tn a
S u s i tn a
tna
La
ke
ee
p
e
lke
Sh
Kas
h wi tna
Skwentna
tan
Ma
Wi l l o w
Lit
tl
s it n
e Su
u sk a
Mat-Su Basin - Biological Value
Chum Salmon Spawning
Major Streams
a
Chum Salmon Spawning - ADF&G
Watersheds with Chum Salmon Spawning
documented spawning
0
The Alaska Department of Fish and Game codes all anadromous waters by species and
lifestage. This map highlights Chum salmon spawning stream segments. These streams are
intersected with the watersheds which are scored 1 for documented presence and 0 for
absence. A total of 67 watersheds contain documented chum spawning. The data used for
this map will be updated over time as we learn more about Mat-Su salmon and their habitat,
which could result in changes to this map in the future. Interpretation of this data is most
appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
0
Cook
Inlet
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
Alaska Dept. of Fish and Game - Anadromous Waters Catalog - 2008.
Map 7
S u si tna
a
Ta
Ch
u
n
l it
Alaska Department of Fish and Game
maintains a Catalog of Waters Important for
the Spawning, Rearing or Migration of
Anadromous Fishes that documents
spawning, rearing, and presence of
anadromous fish and some resident fish.
Documenting anadromous waters in Alaska is
complicated by remoteness, short field
seasons, and limited number of biologists.
Surveys may not capture lifestage
information due to varying timing of return of
spawning adults of different species and
seasonal movement of rearing juveniles.
Currently the catalog contains less than 5000
miles of the more than 23,900 miles of
mapped streams in the Mat-Su Basin.
Despite providing an incomplete record of
salmon habitat, the catalog can be used to
identify patterns of salmon habitat
distribution across the Mat-Su Basin.
e t na
La
Sh
es
ke
D
ee
p
lke
Using the catalog, this map counts how many
of the five Pacific salmon species have been
documented in each watershed. This count
should be viewed as a minimum number of
salmon species in each watershed. For those
interested in restoration or protection
activities that may have the most benefit for
the greatest number of species, this map can
provide guidance.
hk
Mat-Su Basin - Biological Value
a
roto
i l tn
a /K
Kah
S kwentna
Kashwitna
n
Ye
hu
litna
t na
c
Tala
Ma
Wi ll ow
L
eS
ittl
us it n
Salmon Species Richness
ska
t anu
Salmon Species
Documented by Watershed
a
1
3
2
4
5
Species count by watershed is a minimum;
additional species may be present yet undocumented
0
All anadromous waters for each species are merged, then intersected with the watersheds
and finally total species counts for each watershed are tallied. Salmon richness value is
normalized so that watersheds with five species are scored 1, those with four are scored at
4/5 = 0.8, those with three at 3/5 = 0.6, two species are 0.4, and one species is 0.2. The data
used for this map will be updated over time as we learn more about Mat-Su salmon and
their habitat, which could result in changes to this map in the future. Interpretation of this
data is most appropriate at the subwatershed or larger scale.
map by The Nature Conservancy: M. Geist, 2009
0
Cook Inlet
10
20
20
40
Miles
40
Kilometers
80
DATA SOURCES:
Anadromous Waters Catalog, Alaska Dept. of Fish and Game - Sport Fish
Division - 2008.
Map 8
Landcover
Overview
The presence of lakes and wetlands indicate
amount of juvenile salmon rearing and sockeye
salmon spawning habitat potentially available
within a watershed. Wetlands are typically
defined by one or more attributes: the substrate
is periodically or permanently saturated with
water; periodically the land supports waterloving plants such as cattails, rushes, or sedges;
or the area contains undrained wet soil which
lacks oxygen. Within the Mat-Su Basin,
wetlands are associated with lakes, rivers,
uplands, and the coast and may have emergent
plants, shrubs, or forests.
Wetlands play multiple roles in providing
healthy habitat for salmon. They store and
release groundwater slowly, serving to moderate
streamflows and lake levels. Wetlands are
important for groundwater recharge and
discharge, may act as filters to maintain water
quality by removing pollutants and sediment,
and are important for nutrient cycling. Wetlands
provide primary productivity to drive the food
chain. Many wetlands in the Mat-Su Basin are
net receivers of groundwater, which moderates
water temperatures, maintains dissolved oxygen
levels, and prevents thorough freezing in the
winter. If connected to anadromous waters, such
wetlands provide productive rearing habitat for
juvenile fish, and temperature-sensitive
salmonids may seek them for refugia.
Open Water
Perennial Ice/Snow
tn
a
S u si tna
ul
i
Developed, Open Space
Ch
Developed, Low Intensity
Developed, Medium Intensity
Developed, High Intensity
Barren (Rock, Sand, Clay)
Deciduous Forest
Ta
Evergreen Forest
Mixed Forest
lke
e t na
Dwarf Scrub
Shrub / Scrub
ee
witna
Ka s h
a/ K
ro t o
a
ent
i l tn
Skw
Sh
hk
Woody Wetlands
Emergent Herb. Wetlands
es
K ah
Cultivated Crops
D
ke
Pasture/Hay
p
La
Sedge / Herbaceous
na
Mat-Su Basin - Biological Value
Wi l l o w
n
Ye
t na
c
Ta l a
hu
Li tt
le
a
Su s itn
M
at
a
sk
nu
a
Wetlands and Lakes
Wetlands & Lakes
Percent Wetland & Lake Area in Watershed
l itn a
45.0 - 81.6 %
9.0 - 24.8 %
24.9 - 44.9 %
0.0 - 8.9 %
Note: on this map, adjacent watersheds with similar wetland
percentages have been merged for visual clarity
0
National LandCover Dataset has 18 predominant cover types for southcentral Alaska including two
wetland categories: Emergent Herbaceous and Woody Wetlands. These were summed within each
watershed along with the Open Water cover type (lakes, large rivers). The data used for this map will
be updated over time as we learn more about Mat-Su salmon and their habitat, which could result in
changes to this map in the future. Interpretation of this data is most appropriate at the subwatershed or
larger scale.
map by The Nature Conservancy: M. Geist, 2009
0
Cook Inlet
10
20
20
40
Miles
40
Kilometers
80
Data Sources:
Wetlands: National LandCover Dataset (NLCD), USGS, 2008 - based
upon 30 meter pixel LANDSAT imagery collected 1999-2001.
Lakes: National Hydrographic Dataset, USGS, 2006.
Map 9