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February 1997 May 1997 June 1997 September 1997 October 1997 November 1997
February
1997 The marine reserve here at Big Creek was started in 1989
when several local fishermen agreed to set the area aside and
not fish there. Now, eight years later, it is an officially recognized
ecological reserve set aside for marine studies. I just finished
reading six grant proposals for work in the reserve, and it looks
as if this "grassroots" reserve is going to produce
something very worthwhile.
The proposals deal with the value of marine reserves as places
in which fish, abalone, and sea urchins can replenish themselves,
safe from commercial and sport harvesting. The immediate goal
of three of the studies is to count and measure fish populations
inside and near the reserve using a combination of underwater
surveys and fishery monitoring. I believe the underwater surveys
will show that most local fish populations are in a healthy state,
but that in the reserve there are more, larger fish. Larger fish
have proportionately more offspring (millions of larvae are released
in some species), providing a source for new recruitment up and
down the coast. The survey may also show that some species are
depleted in areas outside the reserve, such as the Black and Yellow
rockfish, which is caught for the popular live fish market. Having
a reserve enables us to compare natural fluctuations in fish numbers
to those caused by over fishing. Measuring the fishermen's catch
is an important part of the study, because we can correlate fishing
activities to numbers of fish, and begin to get an idea of what
intensity of fishing may be sustainable.
Two other proposals measure genetic diversity in fish, abalone
and urchin populations. A species' genetic diversity gives it
resilience and vigor in the face of natural and artificial pressures,
and we need to know how much genetic diversity is likely to be
maintained within a given reserve. The scientists' prediction
is that species with wide-ranging larvae (such as many rockfish
species) will have relatively greater diversity within the reserve
area, but lesser differences when comparing different areas. One
of the proposals will look at surfperches, fish which bypass the
larval stage entirely and whose offspring probably take up residence
near their parents. In these fish, lots of genetic differentiation
is expected when comparing fish from different areas. The same
finding has already been made for steelhead, probably for similar
reasons.
The deep water survey (50-300 meters deep) will be done by driving
a small submarine, the "Delta" back and forth across
the reserve. This will be one of the first attempts to make accurate
fish counts in this way at these depths. In this case the fish
are relatively poorly known in their habitat, which is too deep
for routine scuba diving, and we hope to find out new things about
the natural history and habitat preferences of the fish.
I believe that we should set aside many more marine reserves along
the coast of California, so as to bring back the great richness
of marine life that belongs here. This can be best accomplished
with the support of the fishers and other local residents. The
Big Creek marine reserve provides an example of how one might
proceed to create reserves in other areas, and the results from
the Big Creek studies will help to define what they should be
like.
Other notes: Spring seems very advanced this year. The manzanitas
are in full bloom, dropping millions of flowers up on the high
ridges, and the shooting star flowers are huge, nourished by all
the rains. Big Creek finally shrank below flood levels in mid
February after three weeks of dry weather. (2/20/97)
May 1997 I am reading a wonderful
report by Matteo Rutherford, a student who completed his senior
thesis project here at Big Creek a couple of years ago. Matteo
studied fungi that live invisibly inside redwood leaves, called
"fungal endophytes". He collected three year old redwood
leaves by counting three tufts backward from the tip of each branchlet;
he selected older leaves because they are more likely to have
fungal endophytes. He put the leaves on ice and took them back
to the lab, where he sterilized the leaf surface by soaking them
in alcohol and bleach solutions for 10 minutes. He then cut the
leaf open and put it on a sterile nutrient plate. The fungi would
then grow out of the leaf onto the agar and make spore "fruiting
bodies." Matteo could then identify the fungus and record
its species.
One of the most common types was a species of "Pleuroplaconema"
which is found only in redwoods. The fungus lives inside leaves,
and is believed to "defend" the redwood by producing
chemicals that repel pest insects and disease organisms. This
may be important since diseases and pests have short generation
times and can evolve new modes of attack quickly. Even though
the trees cannot evolve defenses quickly, symbiotic fungi such
as Pleuroplaconema probably can, and do so to protect their host
tree. In this way (so the theory goes) they may act as a kind
of "immune system" for the tree.
Matteo found that only two out of 12 redwood trees from Big Creek
were thoroughly colonized by Pleuroplaconema, two more were partially
colonized, and eight had minor or no colonization. Seven of the
trees had substantial infections of another, probably harmful
fungus, Nodulosporum. Matteo suggests that, probably as a result
of the Rat Fire in 1985, our trees have lost their normal complement
of the beneficial fungus. To test this idea, he sampled trees
along Rocky Creek, which have not burned for eighty years. All
but two of the Rocky Creek trees were thoroughly colonized by
Pleuroplaconema, and none had substantial infections of the other
harmful species.
Matteo also reported results from other studies on redwood fungal
infections. In every study, 95-100% of trees had some kind of
fungal infection. The Rocky Creek/Big Creek/Big Sur samples are
the only ones in which the total amount is lower (81-94%). This
suggests that as redwood trees reach the dry southern end of their
range, they have increasing difficulty in keeping a healthy population
of fungal endophytes.
I thought it was very interesting to compare harmful and beneficial
fungi. The beneficial fungi are very specialized (for example,
to redwood trees) and do not tolerate changes in the turpentine-oil
content of their host tree (redwoods, like other conifers, have
an extensive system of canals and ducts which contain pinene and
other turpentine-like oils). Harmful species are tolerant of such
changes, and in addition, can digest cellulose (allowing them
to penetrate and kill the cells of the host tree; the beneficial
fungi do not digest cellulose). When fire, drought, or clear cutting
stresses trees, they seem to lose their protective fungi, which
are replaced by more harmful fungi. If the tree survives, the
beneficial fungi gradually reclaim the tree, expelling the more
harmful species. These examples show me how "ordinary backyard"
organisms like redwood trees are actually extraordinary, and that,
if we knew all the details, their lives are probably as interesting
and complex as our own.
Other notes: the red-tail hawks have hatched two chicks in their
nest below Whale Point. They grew from tiny egg-sized "fuzz-balls"
on April 19 to 2 football-sized "fuzz-monsters" on May
5. The parents stay very busy feeding them. When you approach
within 200' of the nest the parents fly up and scream, and the
chicks cower down and try to hide....We saw very few deer fawns
this year in April, but began seeing more in early May. Feynner
has found two fawns killed by bobcats. This is the second time
that we has seen leaves stuffed in the hole in the fawn's side,
made after the bobcat reached in and pulled out the entrails....We
are hosting our eighth butterfly count on May 31 here at Big Creek.
We are having the count early since the summer has advanced so
rapidly this year. (5/20/97/)
June 1997 This year we have seen
single fawns (as opposed to twins), and they have been late in
coming. A doe with a fawn and two young males has been feeding
on the flowers and greenery surrounding my cabin in the canyon
bottom. Last Friday morning I woke up hearing a yelping "yi",
sounding just like a dog with its tail getting stepped on. A few
seconds later I heard the snorting of an angry deer, and guessed
that the doe's fawn had been killed. I got my binoculars and went
outside. The light was dim, but right after I opened the door
I saw a mountain lion run up the slope opposite my cabin. It looked
over its shoulder at me as it ran. It was a stocky, short-legged
lion, heavily muscled. It glided up into a grove of bays and disappeared.
At the same time the lion fled, the doe bounded off in the opposite
direction, still snorting.
I watched the deer for some time, wondering what they would do.
The mother doe kept snorting and after a few minutes she stotted
back to where the lion had been (stotting means bounding up in
the air on four legs at once). She seemed torn between anger and
a desire to attack the lion (which she could not see) and fear
of being attacked. The two males (probably her sons from previous
years) seemed relatively unconcerned, although they also wandered
over and sniffed the area.
A couple of hours later, when the light got better, Sonie Smiley
came out to observe. With her sharp eyes she immediately pointed
out the body of the fawn lying on the slope. Then we saw the mother
come over and lick the fawn. Still later, a loud noise scared
all three deer and they rushed down to the parking area. This
made Pulguero (our little black dog) bark. The two male deer fled,
but the barking seemed to make the doe angry again. She started
snorting and approaching the dog, who was leashed on the porch.
I saw this through the window, and guessed that she might attack.
I rushed outside and the doe ran off. That night, the fawn disappeared.
I guess that the lion came and got it.
Other notes: The coffeeberry bushes are covered with flowers,
and millions of small fuzzy black and yellow bumblebees are swarming
around gathering nectar and pollen. In previous years the bushes
were surrounded by honeybees and bumblebees were uncommon. The
wild honeybees have declined in the past couple of years, because
of the new infectious mite or some other disease. My guess is
that, owing to the honeybees' decline, the bumblebees have had
a super-abundance of pollen and nectar, and have reproduced in
large numbers to "take their place." It is very likely
that wild flowers and many species which are not well-pollinated
by honeybees may have increased seed set and reproduction as the
native pollinator increases. Other species may decline a bit.
The red tail hawk chicks are flying around the canyon now, awkward
and slow on their new wings....Blue belly lizards are laying eggs
now, digging holes in the dirt....It has been 4 1/2 months since
the last rains, almost like September or October in a normal year.
I would like to dedicate this month's "nature notes"
to Fred Farr, who passed away last week. Fred was a good neighbor
to us here at Big Creek, as well as one of the creators of the
Big Creek Reserve and a strong supporter. I wonder how many of
us who love Big Sur and Monterey County realize how much we owe
Fred. One of Fred's specialties was to bring people to Big Sur,
"wining and dining" them, letting the land speak to
them, and getting them to speak to each other. Lots of politicians
and influential people got this treatment, and we (who get to
enjoy Monterey County's natural beauty and relaxed lifestyle)
have been the beneficiaries. Thank you Fred!
September 1997 I injured my
shoulder last month and now have to type one-handed. This "nature
notes" may be short! Recently I hiked up the middle fork
of Devil's Creek, one of the four major streams that come together
to form Big Creek. Also known as "Cuevas" ("caves")
Creek, this fork climbs up through some spectacular cliffs. The
area is fairly remote and although I don't know of any actual
caves, they may be present. At least a dozen springs line the
creek bottom, including some with large flows.
At the confluence of the middle and south forks, the bed of Devil's
Creek is coated with calcium carbonate mineral deposits. The soft
deposits make for good traction and walking up the creek bed is
easy (but watch out for dark green patches that can be very slippery).
Both forks are rich in carbonates, but the middle fork is bright
green. Hiking up the middle fork, you pass an enormous landslide
(which occurred a couple of years ago and blocked the creek completely),
and then you come to a spring seeping out of the banks. Above
this point the creek bed turns a rich light brown color with no
trace of green. As best I can tell, the green color originates
from the seep/springs, and is not present in the creek for two
miles upstream. It is also possible that the landslide contributes
to the green color since it is close by the springs.
What causes the green color? Green algae are probably responsible,
since millions of tiny bright green cells can be seen enclosed
in the carbonate deposits. Perhaps it requires a special nutrient
which is rare in the sources upstream but which is concentrated
in the seep springs/slide area. The phenomenon is long lasting,
for I observed the same thing when I hiked up this fork over a
year previously. It never ceases to amaze me how distinct the
different forks of a stream can be.
Other notes: I read Tui Anderson's undergraduate thesis yesterday,
reporting the results of his study of the kelp beds in the marine
reserve. The project was designed to see if the kelp canopy at
Big Creek inhibits the growth of understory kelp by shading. It
has already been demonstrated that giant kelp shading occurs,
so Tui wanted to look at other kelps. He chose bull kelp and two
"subsurface canopy" kelps, Laminaria and Pterygophora.
He and several volunteer field assistants made many dozens of
scuba dives over a four month period, experimentally cutting kelps
and measuring the cover of the understory plants. After several
months, Tui found little effect of shading, except under the adjacent
giant kelp. There he saw a reduction in understory cover. Although
disappointing, the "negative" results are important,
showing how certain kelp beds do allow a lot of light to penetrate
and support a rich understory growth, even in summer. Tui is to
be congratulated for completing an extremely difficult, demanding
project. (9/19/97)
October 1997 Last week I noticed
large numbers of tanoak acorns lying under the trees, mingled
with millions of deer hoof prints. This is great news for the
deer and other wildlife, especially the acorn woodpeckers that
have had few acorns in past two years. The annual statewide acorn
survey (conducted by researcher Walt Koenig at Hastings Reserve
in Carmel Valley) indicates that this is a "medium"
year in terms of acorn production. It may sound funny to do an
annual acorn survey, but remember that acorns may be single most
important food supply for our wildlife statewide. A "mast"
acorn crop is a major ecological event, ranking with extreme wet
or dry rainfall years.
I also noted a lot of California Bay fruits under some trees.
The fruiting patterns of the bay are curious to me; in this and
other years I have noticed how some trees bear copious fruit and
others seem barren, even same-size trees growing side by side.
I wish I knew more about this species of tree. I recently obtained
a bibliography about California hardwood trees, and I hope to
track down some literature.
With deer up on the slopes eating acorns, it is time to look for
mountain lion tracks on the roads. The other day I saw two sets
of tracks on the same day. One set was from a smaller animal;
I suspect they belonged to the "girl", a small but powerful
female that we have observed and photographed for the past two
years. Her tracks were 70 mm wide (about 2 3/4").
The width of a lion's track is a good thing to measure since the
width of all four feet on a lion is always about the same. The
hind foot is usually 1/2" or more longer than the front and
the key for a good measurement is to find an isolated track. In
most cases the track of the hind foot is superimposed on that
of the front foot. Look carefully!
A larger lion made a male the other set of tracks, perhaps a male.
These tracks were over 85mm wide (3.25"). The next day our
reserve steward Feynner saw the two tracks together. Perhaps the
larger one was following the smaller. We suspect the large one
may steal deer kills from the "girl" (we found evidence
of this two years ago), or perhaps it may be courtship.
I also saw a large male bobcat bounding off the road. I examined
the ground and found some tracks; they were the same shape as
the lions' but only 45mm wide (1.75").
Other notes: We have had lots of research activity in the marine
reserve recently. The "Delta" submarine made dozens
of dives and reported that lots of the bottom habitat in the deeper
waters (100-300' depth) consists of coarse gravel out of which
grow sea pens. Sea pens are feathery creatures related to corals
and anemones that wave long stalks up out of the gravel into the
water. They filter plankton from the water to obtain food. Mary
Yoklavich, the lead scientist of the project (Mary works for the
National Marine Fisheries Service), says the sea pen beds are
loaded with tiny juvenile rockfish. These fishes are small enough
to hide in the sparse cover Mary and Dave VenTresca (Department
of Fish and Game) are preparing a map of the marine reserve which
will show the bottom types and estimate the number of the different
kinds of fishes there. The researchers have braved tough conditions
with wind, chop, and huge swells to make their dives.
Yesterday I saw a juvenile Peregrine Falcon on the cliffs above
Big Creek cove. Peregrines are easily recognized by their heavy
pigeon-shaped body and their rapid but shallow wing beats when
flying. They specialize in hunting birds along the coast. This
bird seemed inexperienced. I watched it swoop and dive ineffectively
many times, harassing terns and some smaller bird that I could
not identify. As I watched through my binoculars, the falcon flew
out of sight over the open ocean, at least a full mile from shore,
perhaps further. I didn't realize they would stray so far from
land. (10/15/97)
November 1997 The rains finally
came, and California "spring" began. Millions of tiny
seedlings and sprouts appeared along the roads and trails, of
miner's lettuce, clover and sorrel. Buds are sprouting too, on
thimble berries and currants. One currant by our house put out
its first blossom, but this plant gets watered and I think it's
too early yet for the wild ones. The red columbines started blooming
also. Many of these new shoots are tasty to quail, towhees, deer,
and other animals, so it's like a brief spring "salad"
out there.
The yellow banana slugs are out looking for food. They lie dormant
during the dry season, sealed against desiccation in the moistest,
coolest place they can find. This has been a particularly long
dry season (over nine months) and they are very hungry. If you
pick one up and put it on your finger they begin rasping your
skin, which is how they feed on mushrooms and other soft foods.
Some slugs carry mites that live on their bodies. Kim and I looked
at eight slugs the other day on a walk - only one large one had
a population of mites.
These kinds of mites may be an example of how nature can sometimes
favor helping, or "mutualistic" relationships. This
has been studied a lot in carrion beetles (I wrote about Big Creek
carrion beetles and mites in the February 1992 Nature Notes) but
no one to my knowledge has studied banana slug mites. Do mites
feed on the slug, or just on the slugs' food? Do mites help the
slugs survive in any way, or are they parasitic? Clearly the slug
provides shelter and transportation for mites, as well as possibly
a safe way to spend the summer dry season. Are these mites specific
to banana slugs, or can they be found elsewhere? The questions
can go on and on, and if someone would "dig in" and
study this first hand, I predict that many of their answers would
be surprising.
I always see banana slugs along the highway in front of the reserve
(I saw two in the highway turnout in front of our mailbox the
other day). I wonder if they are common residents of the coastal
bluffs? It seems possible because this habitat is generally cool
and damp. However, it also seems likely that the slugs wander
out onto the highway from their home in the redwoods, perhaps
in search of food. Does anyone know of banana slugs living in
non-redwood habitats in Big Sur?
Other notes: Even though we got 3-4" of rain, the creek only
rose 2". Nearly all the rain soaked in, watering the plants
and soil. The creek is the color of tea. This shows that the rainwater
that did make it into the stream has filtered through the leaf
litter and the soil....Sorrel and many other plants made it through
the dry season without being heavily grazed by deer or other creatures.
This indicates that better food was available this autumn, such
as the good acorn crop and the vigorous shrub growth we experienced.
It may also indicate a reduced number of deer in the area. The
two lions which have been continuously present this fall may have
reduced the deer numbers or caused them to shift to safer areas.
(11/21/97)