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Current human interests in kelp within the MBNMS
are as a harvestable resource, a recreational
destination, and ecological habitat. Kelp is
harvested for various purposes in the MBNMS, such
as for abalone feed. Other interests in kelp use
are more complicated, but include: fishing (both
recreational and commercial), recreation (e.g.,
SCUBA diving, boating and wildlife viewing),
education, and scientific investigation.
3.1 Kelp as a Harvestable
Product
3.1.1 History and
Existing Status of Kelp Harvesting
While little is known of pre-historic native
inhabitants' lifestyles along the MBNMS, it is
known that seafood contributed to their diets
(Minerals Management Service, 1990). Therefore,
as there are a number of local algal varieties
that are edible, it is not beyond reason that
some local marine algal species were consumed by
them (Dawson and Foster, 1982).
The first documented historical harvest of
marine algae in the MBNMS was by Chinese
immigrants. As early as the 1850's, Chinese
immigrants were harvesting marine algae in the
MBNMS, drying it, and exporting it to China
through San Francisco (Terrell, 1995). In fact,
the first "mariculture" (i.e., marine
aquaculture) in the area was done as early as
the 19th century by Chinese immigrants who
burned intertidal patches around the Monterey
Peninsula to facilitate red algal recruitment,
which was then harvested for food. The patches
were essentially maintained like plots on a
farm. In 1929, the red algae harvest totaled 135
tons dry weight (Bonnot, 1931).
The first use of kelp in California on a
large commercial basis was for the purpose of
producing potash (potassium carbonate) during
the First World War (Figure 6). At the time,
potash was a necessary ingredient in the
production of gunpowder. The potash was derived
from the kelp ashes after it had been burned. At
that time, kelp was harvested by encircling a
stand of kelp with a cable and then pulling on
the cable (Foster and Scheil, 1985). This
generally had the effect of ripping out the
entire kelp plant, including the holdfast. By
comparison, today's harvest methods are limited
to crop the fronds, which are shortlived
compared to the holdfast (see section 2.5.4
Seasonal Patterns and Kelp Life Histories).
By the mid-1980's, the kelp industry was
worth about $40 million statewide (Tarpley,
1992). Kelp that is harvested in California
today is primarily used in chemical industrial
applications. Algin, which is a product that is
derived from kelp, is used as an emulsifier in
processed foods (Frey, 1971) and other products
where a smooth texture is required (e.g.,
paints, cosmetics, pharmaceuticals). Other uses
of kelp are as food for cultured abalone, and as
substrate for the herring-roe-on-kelp fishery
(exported for Sushi).
South of the Monterey Peninsula (Figure
7 and Table 2), most kelp
is harvested by large vessels, between 140 and 180 feet long
and capable of cutting as much as 600 tons of Macrocystis in
a day for the chemical industrial applications mentioned above
(DFG, November, 1995). These large vessels cut the kelp canopy
about four feet below the surface with the use of subsurface
cutting devices on their stern (similar to how a hedge trimmer
cuts). This is done as the ship backs down through a kelp bed
(Foster and Schiel, 1985).
ISP Alginates Incorporated (formerly known as
Kelco) is almost exclusively the harvester of
kelp south of the Monterey Peninsula. There are
two abalone mariculture facilities, and several
herring-roe-on-kelp fishermen that occasionally
harvest kelp around the Cambria area, and very
occasionally further north. ISP Alginates has
been harvesting kelp off the coast of California
for over 70 years. ISP Alginates harvests kelp
to extract algin. ISP Alginates employs
approximately 170 people in California, has $40
million in annual sales from California
productions of $40 million, and a $20 million
annual California payroll (Dale Glantz, pers.
comm.).
While ISP Alginates major operations are in
Southern California, it occasionally will cut
kelp in the MBNMS in the late summer and early
fall along the Big Sur coastline. In recent
years, ISP Alginates' operations have extended
north of Point Sur. For example, in 1998, for
one day, an ISP Alginates' boat did harvest as
far north as Carmel Bay (Dale Glantz, pers.
comm.).
Kelp harvesting on and north of the Monterey Peninsula (Figure
7 and Table 2) is primarily
by hand and is utilized for abalone feed, and, to a very limited
degree, recreational, educational, scientific purposes, and
for the herring-roe-on-kelp fishery. Hand-harvesting of kelp
is typically done from small skiffs. Hand-harvesters reach over
the sides of the skiff and cut the kelp fronds just below the
surface (DFG regulations state that kelp cannot be cut further
than four feet from the surface). The kelp is then hauled aboard
the boat. In this fashion, up to two tons can be harvested on
any one trip in the typical skiff. Once cut, that particular
kelp frond stops growing. The kelp plant continues growing from
other fronds that have not been cut, or by starting more fronds
from the holdfast.
The first abalone mariculture operations in
the MBNMS, utilizing kelp as an abalone food
source, were on Monterey's Cannery Row, and at
Pigeon Point in San Mateo County, in the 1960's.
Abalone mariculture enterprises that utilize
kelp in the MBNMS today are limited to three
abalone facilities: one in Davenport, and two in
Monterey Harbor. Two other abalone farms lie
just outside the MBNMS to the south. To hold the
abalone, the facility in Davenport pumps ocean
water into onshore holding pens (or "raceways"),
while the two Monterey facilities rely on
floating pens. The abalone in the pens are fed
kelp that is harvested from nearshore kelp beds.
The abalone mariculture operations in Monterey
Harbor are relatively small operations (in terms
of the number of abalone held) compared to the
Davenport operation, or the combined operations
proposed for Pillar Point Harbor (see
below).
Economically, all of these operations
contribute to the local general economy,
particularly to the tourist industry. Many local
restaurants serve abalone on their menus. Due to
the recent closing of California's commercial
abalone fishing industry, maricultured abalone
is the only available source for these
restaurants. Besides the abalone meat, the
shells are utilized as curios and as jewelry.
U.S. Abalone, for example, has recently marketed
a line of jewelry based on cultured abalone
"pearls", and is marketing them locally (David
Ebert, pers. comm.).
3.1.2 Present Kelp
Harvesting Levels
In California, the State may lease, through an open competitive
public process, certain kelp beds to individuals or companies.
The price paid for a leased bed may therefore vary. Leased beds,
which can only be harvested by the tenant, enable companies
to more efficiently plan and manage their kelp harvests. Open
beds (i.e., unleased beds) can be harvested by any individual
or company with a valid DFG kelp harvesting permit. "About 38%
of the State's kelp beds have been reserved for harvest by any
licensed kelp harvester. No leasing of these beds is allowed.
This policy insures that the State's smaller kelp harvesters
will have access to kelp, and will not be shut out by lease
agreements with large companies" (DFG, November 1995). The total
tonnage of kelp removed from California kelp beds in 1994 was
approximately 81,006 tons (Figure 6).
Of this amount, approximately 54,682 tons (67.5%) were from
"leased beds", while the remainder, 26,324 tons (32.5%), was
from "open beds" (DFG, November 1995).
The number of leased beds in the MBNMS, and California in general,
may fluctuate from year to year as leases expire, are renewed
or are newly acquired. In 1999, there were four leased beds
and 16 open beds in the MBNMS (Figure
7).
The total tonnage taken from the MBNMS kelp beds fluctuates
widely also. In 1992 and 1993, there were 10,323 and 6,659 tons
harvested respectively (Table 2).
However, due to storms in 1994 which limited access and available
kelp, only approximately 551 tons were taken (Table
2). In 1995, total harvests taken from MBNMS kelp beds was
back up to 5,201 tons (Table 2).
Therefore, the total amount of kelp harvested in the MBNMS varies
greatly due to various factors such as weather (Figure
8) or availability of kelp in other locations around California
(Dale Glantz, pers. comm.).
Within the MBNMS, kelp harvesting has historically been concentrated
near Cambria, Point Sur, and from Carmel Bay to Monterey Bay.
However, north of Point Sur, there has historically been little
to no commercial harvests of kelp (Table
2).
Around the Monterey Peninsula (CDFG Kelp Bed
#220), kelp harvest levels have been declining
from a high in 1996 (664 tons). By 1999,
harvests were only 21% (142 tons) of this total.
Reasons for this decline in harvests include
social pressures to harvest elsewhere,
oceanographic conditions, collectivization of
harvesting efforts under the Monterey Kelp
Cooperative, and abalone facility business
failures.
Recently, the California Coastal Commission
and the San Francisco Bay Regional Water Quality
Control Board approved four permits to start
abalone mariculture operations in Pillar Point
Harbor. The MBNMS reviewed those Pillar Point
abalone proposals, and wrote several comment
letters to the California Coastal Commission and
DFG. While the proposed new facilities are
inside the harbor, and therefore outside the
area jurisdiction of the MBNMS, the kelp that
will be needed to sustain such operations will
probably come out of the MBNMS. At full
buildout, these four facilities will contain as
many as 2.25 million abalone (up to 3 inches in
diameter). Coastal Commission staff estimates
that the amount of kelp needed to sustain this
buildout, up to 1,800 tons per year*, could be
of concern depending where, and how frequently,
the harvests are made (see the California
Coastal Commission staff reports on these four
projects passed out at the July 15, 1999,
Coastal Commission Public Hearing).
While concerns over some localized harvests
continue to exist, MBNMS concerns about
increasing harvests of kelp within the MBNMS
have been greatly tempered since the first
release of the MBNMS Kelp Report in January. The
MBNMS has been informed by ISP Alginates that
their harvest levels in the MBNMS, and
California in general, have decreased by half
since 1993 (Dale Glantz, pers. comm.). This is
due to the fact that ISP Alginates decided to
move many of its lower-grade production
facilities to Scotland, and only conduct
high-grade production of alginates in
California. The MBNMS encouraged DFG to tabulate
this recent harvest data early in its Kelp
Management Report review process so that the
people of California can more accurately review
the status of the industry. Also, within the
last year, a major kelp harvesting interest in
the MBNMS, Pacific Mariculture Inc. (PMI), based
in Santa Cruz, went out of business. The
withdrawal of PMI from the kelp harvesting scene
has reduced the number of maricultured abalone,
hence harvested kelp, by nearly one-half.
* - Local abalone
aquaculturalists claim this is an
overestimate of kelp needed for the Pillar
Point projects, and believe a more accurate
estimate should be about half that amount.
The harvesting community support this claim
with data generated by various researchers
(Godoy et al., 1992; Godoy and Jerez, 1998;
McBride, 1998) as well as their own
experiences. The MBNMS itself does not have
sufficient data at this time to provide an
accurate estimate of how much kelp is
actually needed by an abalone aquaculturalist
based on the size of their operations. The
MBNMS believes this information is crucial to
a healthy public discussion of the issue. The
MBNMS would encourage DFG to publish such an
estimate in the first draft of their CEQA
document so that public process can continue
based on an independent, public agency
generated estimate.
3.1.3 Ecological Effects
from Kelp Harvesting
Even under ideal conditions, where plenty of
management funding and labor resources exist,
precise human management of kelp forests is
inherently difficult due to the complexity of
the ecology and the highly dynamic marine
environment of kelp forests (Foster and Schiel,
1985).
The question of the effect of kelp harvesting
on kelp forests is of interest to the MBNMS.
After an analysis of the studies that have been
done, two general conclusions can be reached.
The first is that when kelp harvesting is done
on a limited scale, there is generally little
detectable, adverse effect on the kelp forest.
The second conclusion is that, while numerous
expert opinions agree that overharvesting can
occur (North, 1968; Miller and Geibel, 1973),
and have even postulated as to the parameters
for such a harvest level, few long term studies
exist that can answer the question, "At what
point would intensive repetitious harvesting,
especially in a confined space, begin to cause
significant ecological impacts?" Such a question
becomes even more complicated when
non-harvesting impacts, such as storms,
nearshore development, incidental effects from
recreational uses of the kelp bed, and sewage
discharges, such as those activities that occur
in CDFG Kelp Bed #220, are factored in.
The studies that indicate little to no effect
from limited harvesting are numerous, though
focused on only several aspects of the kelp
forest ecology. These studies address both the
effects on the kelp plant/canopy itself, as well
as some of the associated organisms of a kelp
forest. However, further studies are needed as
some aspects of kelp harvesting have only been
partially studied, or not studied at all (e.g.,
effect on benthic invertebrates, marine mammals,
sea birds).
While Miller and Geibel (1973) did find that
kelp abundance declined slightly when an area's
kelp canopy was repeatedly removed, they
generally concluded that the effect was not
significant. Other studies (Barilotti et al.,
1985; Donnellan and Foster, 1999) have also
found that no significant effect on the kelp
canopy from harvesting could be discerned,
especially when time frames of more than a year
are investigated. This may be due to the highly
variable nature of the environment, few data,
and an inability of researchers to determine the
cause of single year observations.
Removal of a kelp canopy can have significant
effects on increasing growths of subsurface
algae by allowing more light to penetrate the
water column (Pearse and Hines, 1979; Reed and
Foster, 1984; Breda and Foster, 1985; Harrold et
al., 1988). Most recently, Clark et al. (in
prep) showed that this phenomenon was true, but
not for all algal species. While it is apparent
that canopy harvesting can have an effect on
growths of subsurface algae, other factors such
as wave exposure (Breda and Foster, 1985;
Harrold et al., 1988; Graham, 1997),
Additionally, El Niño events (Dayton and
Tegner, 1984; Dayton et al., 1992), and
temperature/nutrient fluctuations (Zimmerman and
Robertson, 1985) could all have effects on algal
species composition and abundance. Kelp
harvesters have argued, and some studies support
the concept (Kimura and Foster, 1984; Clark et
al., in prep.), that limited kelp harvesting can
actually increase the amount of kelp
availability in an area by allowing more light
to reach the bottom (in addition to other
benefits - see Section 4.3 - Use Conflicts
below), and thereby increase the amount of kelp
recruitment. While kelp harvesting leading to
increased light penetration may increase the
number of kelp recruits, the biomass of kelp may
actually decrease because the recruits are much
smaller, and intraspecific competition will
reduce the plant density as the recruits grow
toward the surface.
Invertebrates, of all the groups of species
that rely on kelp forests for their habitat, may
be the most affected by kelp harvesting. For
motile invertebrates in the kelp canopy,
previous studies estimate that from 1/4 to 1/3
of them are removed when kelp is being harvested
by large scale harvesters (Quast, 1968).
However, no research has conclusively determined
whether or not such removals are significantly
affecting those species populations within the
forest, or if such removals are ecologically
important. Hunt (1977) did find significant
reductions in a species of turban snail in
harvested areas as compared to non-harvested
areas. A recent class study by students at the
University of California, Santa Cruz, indicated
harvests of canopy invertebrates may be higher
than previously thought (Ish and Reisewitz,
1999). Virtually no studies can be found that
analyzed the effect of kelp harvesting on kelp
forest benthic invertebrates.
The effect of kelp harvesting on
invertebrates attached to kelp fronds (e.g.,
gastropods, crustaceans) is poorly understood.
Therefore, MBNMS staff have preliminarily begun
working with University of California scientists
to outline studies that better assess the
potential effects of kelp harvesting on these
species. It is noted that some very small,
immobile invertebrates (such as bryozoans) that
are harvested along with the kelp are usually
consumed by the abalone as part of their diet
(Dave Ebert, pers. comm.).
Quast (1968) summarized three studies that
examined the effect of kelp harvesting on
finfish populations. All three of the studies,
each using a distinctly separate means of
analysis, indicated that little to no affect
could be discerned from kelp harvesting. Miller
and Geibel (1973), through several experimental
methods, also concluded that adult fishes were
probably not affected by kelp harvesting, though
they raised some concern for juvenile fish
concentrations, particularly juvenile rockfish,
due to harvesting. Other DFG biologists have
made similar observations and relayed these to
the MBNMS (Robert Lea, pers. comm.). These
observations indicate that more studies need to
be conducted on this matter. The few studies
that exist are many years old and concentrated
in Southern California.
No experimental studies were found that have
analyzed the effect of kelp harvesting on
seabirds, despite the fact that birds are
commonly seen foraging in and around kelp
forests.
A particular issue of concern to the
conservation community is the effect that
concentrated kelp harvesting, as well as other
activities (e.g., recreational), could be having
on sea otters. This is especially true in light
of recent downward trends in the California sea
otter population (though this trend appears to
have been reversed according to the most recent
Fall and Spring sea otters counts). As stated
previously, sea otters feed on various
invertebrates that exist in kelp forests (Foster
and Schiel, 1985; Ostfield, 1982), and utilize
kelp forests as a natural refuge and as nursery
areas (Foster and Schiel, 1985). No experimental
studies could be located that analyzed the
indirect effect of kelp harvesting (i.e.,
potential loss of habitat and food) on sea
otters. However, it has been shown that sea
otters are very adept at prey switching when a
preferred food item is unavailable (Ostfield,
1982). This ability of sea otters to readily
switch prey would make experimental studies
difficult on the indirect effects of canopy
loss. Indications are that little direct
physical threat to the sea otter is likely from
mechanical harvesting (Fulton and Saunders,
1985; DFG, November 1995). In a study of human
disturbances to sea otters in some areas where
kelp is harvested, Curland (1997) did not
collect data on this activity as regarding its
affect on sea otter behavior. No other studies
can be found that have investigated the effect
of kelp harvesting on other marine mammals that
are found in and around kelp forests, such as
harbor seals and sea lions.
Another environmental concern that needs to
be mentioned is the importance of drift kelp and
"wrack" to the ecology of various ecosystems. In
the subtidal environment, drift kelp is an
important food source for various organisms such
as abalone and sea urchins (Foster and Schiel,
1985). On the beaches, kelp wrack is an
important food source and habitat for numerous
organisms (Oakden, 1996). In the deep benthic
environment of areas in the Monterey Bay
submarine canyon, kelp may provide an important
food to the organisms found there (Harrold and
Lisin, 1989; Okey, 1997; Harrold et al., 1998;
Okey, in prep.). Finally, in the epipelagic
zone, floating kelp masses are important habitat
for juvenile fishes, such as rockfish (Foster
and Schiel, 1985; Aaron King, pers.
observ.).
As stated above, when the MBNMS first began
investigating this issue several years ago, it
was apparent that no studies have been
successfully completed that would help indicate
when (or if) intensive and repetitive harvesting
in a confined space would begin to be
ecologically significant. A 1998/99 study funded
by the MBNMS, as well as the cities of Monterey
and Pacific Grove, was attempted using existing
data, and looking at the long term effect of
kelp harvesting in a small confined space (the
area along the Monterey Peninsula coastline from
the Coast Guard Breakwater to Lover's Point) on
the kelp canopy. This study, by Michael D.
Donnellan and Michael S. Foster (Donnellan and
Foster, 1999; Appendix 3), utilized aerial
photos and harvest records dating back to 1972.
The study indicated that kelp harvesting had
little to no effect on the kelp canopy at or
near peak canopy cover months. However, the
study was inconclusive because low sample sizes
and high variability in kelp abundance limited
the statistical power of the study design.
Further aerial surveys being conducted by the
MBNMS (see below) will add to this database and
allow follow-up on this study to eventually
produce more conclusive results. In particular,
the MBNMS is looking for more conclusive results
regarding effects during seasons when kelp
canopies are lower and "competition" for kelp by
other users is more pronounced.
During the comment period for the first
release of the MBNMS Kelp Report, the issue of
Nereocystis utilization by kelp harvesters was
raised. As stated above, north of Santa Cruz,
the bull kelp, which occurs from Point
Conception to Unimak Island in the eastern
Aleutians, becomes the dominant canopy-forming
kelp. However, none of the Nereocystis beds in
the MBNMS appear to be of any great size (Van
Wagenen, 2000).
The effects of Nereocystis harvesting on the
abundance and distribution of Nereocystis have
been studied in British Columbia (Foreman,
1984). These studies can find little effect from
harvesting at the site scales investigated,
though Roland (1985) found that harvesting
fronds can impede plant growth and
reproductivity. However, Nereocystis is an
annual plant (Macrocystis is a perennial plant),
is limited in its MBNMS distribution, spore
production is seasonal (late spring to the death
of the plant in winter), and harvesting of
Nereocystis removes the reproductive tissue
(unlike with Macrocystis harvesting) (DFG,
November 1995). Therefore, there is a valid
issue regarding the effect of localized,
concentrated harvests of Nereocystis in the
MBNMS. Such concerns would be particularly
realized if such harvests occurred prior to
spore release. California restricts harvests of
Nereocystis north of Point Arguello (California
Code of Regulations: Title 14, Section
165(c)(4)), because the beds are too important
to the ecology in those areas. They also
outright bans harvests in certain kelp beds
north of San Francisco (DFG Kelp Beds #303, 304,
305, 306 and 307) because their production is
too variable to allow harvest (Robson Collins,
pers. comm.).
As part of developing a long-term kelp canopy
monitoring program, and building on previous
work by DFG and the Monterey Bay Aquarium, the
MBNMS funded aerial mapping surveys of kelp
canopies in the early fall of 1999 (Van Wagenen,
2000). In 1999, with the return of cooler waters
during the recent La Niña conditions,
tremendous kelp canopy cover was found along the
MBNMS. These 1999 data from the overflight were
compared to data from a similar overflight
project conducted by the same contractor for DFG
in 1989. Visually, the size, shape and extent of
the kelp beds along the MBNMS were very similar
between the 1989 and the 1999 overflights. One
very obvious similarity between the two datasets
was the near complete lack of kelp beds north of
Año Nuevo, with large beds occurring just
south of that point. This is noted even though
these overflights occurred at (or near) the peak
of the kelp canopy height. Also, in the case of
1999, kelp production was very high along the
central California coast.
The total Sanctuary-wide kelp resource canopy
decreased from 16.918 square miles in 1989 to
14.053 square miles in 1999. The greatest loss
in kelp canopy extent between the two
inventories was observed within the Monterey Bay
itself (DFG Beds #222, 221 and 220), and the
greatest gain in kelp resource extent was noted
in DFG Bed #217, between Yankee Point and Point
Sur (Van Wagenen, 2000). [NOTE: Caution must
be used in reviewing and comparing these data,
which actually only represent two data points,
separated by a ten year period. These data do
not necessarily reflect long-term trends in kelp
resource extent and distribution (Van Wagenen,
2000). Caution must also be extended to the idea
that deciding on a point in time when kelp is at
its maximum extent BEFORE the overflight occurs
is challenging.]
The MBNMS plans to continue the aerial
surveys each fall to document canopy maximums,
and potentially each late winter/early spring
when kelp canopy cover is typically at its
minimum. It would also be useful to study
short-term canopy variability. After annual
overflights have been done for a long enough
period of time, these data are expected to
reveal long-term trends in kelp canopy extent.
Canopy data will be integrated with other kelp
community surveys being conducted by regional
scientists and institutions.
As stated in the beginning of this section, a
need exists for an answer to the question, "At
what point would intensive repetitious
harvesting, especially in a confined space,
begin to cause significant ecological impacts?"
Abalone mariculturalists need kelp on a ongoing
basis. They need kelp during the winter (when
kelp supplies are low), as much as they need it
during the summer (when kelp supplies are high).
During times of low kelp abundance (e.g.,
winter, after storms, and during El
Niños), it stands to reason that any
environmental effect that may be occurring is
most likely compounded by harvesting larger
percentages of the kelp canopy during these
times. Any management strategy should have a
consideration about protecting areas that could
be potentially overharvested in times of reduced
kelp canopy cover.
It should also be noted in this section that
there may be distinct differences in
environmental effects caused by mechanical
harvesting versus hand-harvesting. Many of the
studies mentioned above, such as Miller and
Geibel (1973), investigated kelp harvesting
situations that more closely resemble effects
that mechanical harvesters create.
Hand-harvesters generally do not cut as deep or
in as distinct a pattern as mechanical
harvesters (Aaron King, pers. obs.; David Ebert,
pers. comm.). No studies are known that describe
any environmental effect differences between the
two methods of harvest.
The effect of kelp harvesting on the
environment must also be placed into perspective
as it compares to natural events. Storms, and
other natural events, can have a significant
effect on the amount of kelp available in an
area over a very short period of time (Miller
and Geibel, 1973; Foster and Schiel, 1985). El
Niño conditions can aggravate the low
kelp abundance after winter storms by reducing
the growth of kelp (DFG, November, 1995).
Finally, along the area of CDFG Bed #220, it has
been estimated that as much as 200,000 tons of
wet weight drift kelp are generated per year
(Harrold et al., 1998). Considering the
hand-harvested area from Point Pinos to the
Coast Guard Breakwater accounts for about 1/6 of
this area (33,000 tons of kelp), the kelp
harvesting community along Cannery Row harvests
about 2% (1987 to 1999 average harvest = 592
tons) of this production per year (Table 2).
Additionally, a portion of this harvest (it is
unknown how much since records are not maintain
with this information) is collected as drift
kelp by the harvesters, which may come from
other areas.
For further reading, two reports are
recommended that provide an introduction to the
present state of knowledge regarding harvesting
effects on a kelp forest's general ecology.
These are: the "DFG California Kelp Plan" (DFG,
November 1995, Sections 4.1 to 4.8.2); and, "The
Ecology of Giant Kelp Forests in California: A
Community Profile" (Foster and Schiel,
1985).
3.2 Other Uses of Kelp
3.2.1 History and
Existing Status of Other Kelp Uses
The first records of western exploration of the
Pacific indicate that early European sailors
used kelp as a navigational aid to help identify
both nearshore rocks and, further out at sea,
the proximity to land through the sightings of
floating kelp plants (North, 1971). The first
published information on kelp biology was by
Charles Darwin (1860) after his HMS Beagle
voyage.
In recreational fishing (for fish,
crustaceans, molluscs, etc.), kelp itself is not
utilized, but the species associated with kelp
forests have long been sought by fishermen.
Traditionally, kelp forests have not been
heavily targeted in commercial fisheries.
However, in the last few years, commercial
fishing in kelp forests has been increasing to
supply the "live fish" market. In the live fish
fishery, fish are either caught on hooks or in
traps, and then held live for sale. Live fish
can bring several times the ex-vessel price (up
to $9 per pound) than does the same fish sold
dead (about 30 cents per pound) (Griffith,
1998). While these prices reflect extremes in
the market, the concept is that the "Live Fish
Fishery" adds a tremendous amount of value to
the commercial prices for nearshore fish. In
this respect, the non-harvested use of kelp
forests may be very important and economically
relevant.
Major industries have arisen over the past 30
years which can be directly tied to the influx
of tourists to the MBNMS. In 1992, for example,
the counties along the MBNMS had a tourism
industry that generated about $634.9 million in
tourism spending (State Resources Agency, 1995).
Many of these tourists are attracted to the
MBNMS area because of the area's beautiful
scenic shoreline. Kelp beds are an important
component of this nearshore attraction.
Restaurants and hotels located on the coast
are particularly popular. Kelp beds, especially
ones that contain numerous seabirds, sea otters
and other marine animals, provide a pleasant
atmosphere for dining or lounging. In general,
"The beauty of the environment has become the
cornerstone of the region's visitor-serving
economy" (Knight, 1997).
Other more active uses of kelp beds include
SCUBA diving, kayaking, and other sports. Kelp
beds provide the environment that attracts many
of these recreational users to the sport. Most
of these "ecotourism" type industries are on the
increase in the MBNMS area. One business in the
area that rents and sells kayaks, as well as
gives lessons on kayak use, has stated that
between 1989 and 1999, kayak use from its shops
has increased ten-fold (Cass Schrock, pers.
comm).
Likewise, the economic importance of
recreational diving in the MBNMS is undeniable.
The following paragraph by Weinstein (1996),
puts this into perspective:
The Northern California Diver's Association
estimates that the number of divers in the
central coast rose 10-20% in the 1980's (R.
Gallagher pers. comm.). Dive shops from Monterey
Bay to Santa Rosa (north of MBNMS) made $14
million in retail sales in 1994, plus about $5
million in associated revenues such as lessons
and boats. An estimated 95% of this revenue was
generated in the Monterey Bay area (R. Gallagher
pers. comm.). This value complements the
findings of another study estimating SCUBA and
snorkeling revenue at $13.2 million dollars in
1988 for San Mateo, Santa Cruz, and Monterey
counties (Meyer Resources, 1990).
Further, the owner the Aquarius Dive Shops in
Monterey stated that business has increased
about thirty percent over the past ten years
(Harrold Toberman, pers. comm.).
3.2.2 Ecological Effects
from Other Uses of Kelp
Generally speaking, other uses of kelp
resources, while not directly tied to the "take"
of kelp, could have an impact on the kelp forest
and its ecology. Detrimental impacts of
increased visitation in recreational areas is
documented for some systems, though such
documentation is limited for temperate reefs. A
contributed papers session at the 1997 Western
Society of Naturalists focused largely on this
general issue of increasing visitations in
recreational areas. The topic for eco-tourism
and rocky shores in particular, was addressed at
the Sanctuary Currents Symposium in 1998. Of
late, this issue of increasing visitation in
recreational areas has received significant
attention at Yosemite National Park. Locally,
concerns about the over-use by humans of rocky
shores has spawned a recent petition drive in
Pacific Grove, California, to place new
restrictions on use of its intertidal areas. The
Florida Keys National Marine Sanctuary also
considered this issue recently in the
development of its management plan. Finally,
boating, powered and non-powered, is well
documented as having the potential for
ecological damage (Dornbusch & Co., 1994).
Curland (1997) found that human recreation
activities (e.g., boating, kayaking, diving) in
the kelp forest along Cannery Row can have
impact (though perhaps not significantly) on the
behavior of sea otters. For a further discussion
of this issue, see the MBNMS Site
Characterization section on "Human Uses" at:
http://montereybay.nos.noaa.gov/sitechar/human.html
As stated above, other uses of kelp forests
include the take of other species associated
with the kelp forests ecology, such as fish and
invertebrates. While a discussion of this topic
is beyond the scope of this report, it should be
noted that this use of kelp forest, such as
recreational/ commercial fishing, and
commercial/scientific/educational collecting,
can also have impacts on the kelp forest
systems. For example, intensive removal of
certain kelp forest inhabitants (sea otters, sea
urchins, etc.) may have significant effects on
the distribution of the kelp forest itself (for
a discussion of this issue, see Foster and
Schiel, 1985).
Although the Monterey Peninsula is a common
destination for SCUBA divers, and gets a high
level of use every year, little information
exists on the potential influence of divers to
temperate reef systems. At Point Lobos Reserve
in the MBNMS, where resource harvesting
(including kelp harvesting) is banned,
recreational use (including SCUBA diving) is
also strictly limited by the State of
California. Studies have not been done at that
site to evaluate how limitations have, or have
not, influenced kelp forests. A wealth of
information exists on diver influences on coral
reefs (e.g., Hawkins and Roberts, 1992 and 1993;
Rouphael and Inglis, 1997) and associated
organisms (e.g., Cole, 1994). In 1998, the MBNMS
partially funded a study focused on potential
diver impacts to kelp forests (Schaefer and
Foster, 1998). While the study observed some
diver impacts, the report states that
determining the ecological effects of these
disturbances would be difficult due to the
natural spatial and temporal variability of
these systems. Thus, the study did not determine
if such effects were ecologically important.
Neither the 1998 MBNMS diving study, nor any
other study that can be located, has
demonstrated that SCUBA diving is actually
producing significant and long-term impacts on
temperate reefs, including impacts on kelp
forests.
A goal of the Monterey Bay National Marine
Sanctuary is to enhance visitor experience while
avoiding negative impacts to resources. A
significant MBNMS focus, program-wide, is on
including education in recreational activities.
For example, the MBNMS has recently initiated
the "MBNMS Diver Partnership Program" to welcome
divers to the MBNMS and enlist their support to
protect resources. For more information on this
project, please see the MBNMS website at:
http://montereybay.nos.noaa.gov/educate/divered.html
Finally, other human uses of the marine
environment in general may have effects on kelp
forests (Foster and Schiel, 1985). Boating
traffic can cause visible effects on a kelp
canopy by cutting surface fronds. Coastal
construction can cause changes in localized
oceanographic conditions, as well as turbidity
and sedimentation (Foster and Shiel, 1985).
Finally, and perhaps most important, water
quality degradation via point source and
non-point source pollution can have significant
impacts on the ecology of a kelp forest. Experts
generally agree that sewage discharge from the
Los Angeles area lead to the complete
destruction of the Palos Verdes area kelp
forests starting in the 1940's. Only after water
quality improvement mandates were imposed did
the kelp forest begin to reappear (Wilson,
1982).
With regard to the areas along Cannery Row,
Santa Cruz and Pillar Point, the recent
accidental releases of raw sewage could lead to
temporary impacts on the local kelp forests and
related industries.
The regulatory agencies must also consider
nearshore development projects on kelp beds,
such as desalination plant discharges, point and
non-point pollution, and large ship (e.g.,
military and cruise ships) traffic, ensuring
that no inappropriate waste releases occur.
3.3 Use Conflicts
Future socio-economic studies are needed to help
the public determine how it best would like to
manage kelp resources managed in the future. Such
studies are, by and large, lacking. As Dr. Caroline
Pomeroy (Researcher, UCSC) stated in her comments
on the first release of this document:
Socio-economic studies can identify and
accurately describe user groups, nature and extent
of their activities, perceptions, attitudes and
opinions regarding the kelp resource, its use, and
the conflict. Socio-economic studies can evaluate
the potential costs and benefits, and impacts
(positive and negative, within and across groups)
of management alternatives. But only society
through the policy making process) can make the
value judgment to determine "the wisest use" of
this resource.
Increased harvesting of kelp in certain limited
areas has led to a number of use conflicts with
other users who also have been increasingly
utilizing these same areas. Two different
industries, harvesters and recreational users,
utilize these same areas for similar reasons. These
reasons include: easy access, relative safety from
open-ocean conditions, and lingering kelp
availability in winter months when large waves
remove plants at more wave-exposed sites.
One area where pronounced use conflicts have arisen recently
is along the Monterey and Pacific Grove coastline, part of DFG
Kelp Bed #220 in the DFG management regime. This bed stretches
from Cypress Point to the Monterey Coast Guard Breakwater (Figure
9). Local kelp harvesters have annually removed an average
of about 377 tons in this area since 1996 (Table
2), with the amount decreasing over that time frame. The kelp
harvesters are particularly interested in harvesting from this
spot during the winter months, when kelp supplies on other, more
wave-exposed coastlines, are low. Additionally, because of the
sheltered nature of this coastline, harvesters and other users
alike are generally safer from the winter waves and other sea
conditions.
At this same time, though it is during the
off-season for tourism, this area continues to
attract a large number of tourist and other
recreational use of the kelp forest resources. For
example, there are five recreational dive shops in
the area, three of which are new in the past ten
years.
While the kelp harvester can legally remove the kelp canopy down
to just four feet in depth, the effect can be an appearance that
no kelp has been left in an area. However, new kelp fronds can
be just below the surface, and, due to its rapid growth (up to
2 feet per day &endash; Clendenning, 1960), can reappear quickly.
The ecological effects of harvest has been discussed previously
(see Section 4.1.3). However, even
if such removals are not ecologically important, they could have
a financial effect on kayak and dive shop businesses. This is
especially true during the winter months, when low kelp abundance
due to storms and other environmental factors is compounded by
slow kelp growth due to reduced sunlight.
During times of winter storms, it has been
suggested that the trimming of the kelp plants
actually reduces drag, and may save plants from
being torn out by waves (Rosenthal, 1974; Graham
1977). Some researchers report finding large balls
of many kelp plants, including holdfasts, entangled
in each other. According to this theory, when one
kelp plant is ripped out from waves, it may
snowball into other kelp plants, increasing their
drag from the waves, and causes them to rip out
also (Rosenthal et al., 1974).
One observation (Miller and Geibel, 1973)
suggested the opposite effect from harvesting. This
study found that repeated harvesting may have the
effect of weakening the kelp holdfast, thereby
making the plant more susceptible to being removed
by storms. However, the simulated harvests from
which this observation was derived were much more
intense than what is even legally allowed today in
California.
No socio-economic studies are available to help
determine the wisest use of a kelp resource that
may, in certain areas, be limited or confined.
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