Biodiversity and Conservation 10: 1949–1962, 2001.
© 2001 Kluwer Academic Publishers. Printed in the Netherlands.
Birds at a Southern California beach: seasonality,
habitat use and disturbance by human activity
KEVIN D. LAFFERTY
United States Geological Survey, Western Ecological Research Center, Marine Science Institute,
University of California, Santa Barbara, CA 93106, USA (e-mail: email@example.com;
Received 18 July 2000; accepted in revised form 3 January 2001
Abstract. Use of a Santa Barbara beach by people and birds varied in both time and space. There were
100 birds, 18 people and 2 dogs per kilometer. Bird density varied primarily with the season and tide
while human activity varied most between weekend and weekday. Bird distributions along the beach were
determined mainly by habitat type (particularly a lagoon and exposed rocky intertidal areas). For crows
and western gulls, there was some evidence that access to urban refuse increased abundance. Interactions
between birds and people often caused birds to move or ﬂy away, particularly when people were within
20 m. During a short observation period, 10% of humans and 39% of dogs disturbed birds. More than
70% of birds ﬂew when disturbed. Bird species varied in the frequency that they were disturbed, partially
because a few bird species foraged on the upper beach where contact with people was less frequent. Most
disturbances occurred low on the beach. Although disturbances caused birds to move away from humans,
most displacement was short enough that variation in human activity did not alter large-scale patterns of
beach use by the birds. Birds were less reactive to humans (but not dogs) when beach activity was low.
Key words: beach, birds, disturbance, dogs, recreation, shorebirds
About half of the shorebird species in North America are in decline, primarily due
to habitat destruction and degradation (Howe et al. 1989; Brown et al. 2000a). The
world’s growing coastal population continues to increase the encroachment of peo-
ple into shorebird habitat (Burger and Gochfeld 1991). A good example is Southern
California, where the climate and culture make beach recreation popular along the
Pacific Flyway. The resulting disturbance from humans and pets degrades habitat for
shorebirds because disturbance may reduce foraging efﬁciency and opportunities for
rest (Burger 1986; Brown et al. 2000b). Chronic, cumulative disturbance could, there-
fore, reduce shorebird reproduction and survivorship. In particular, short ﬂights are en-
ergetically costly for small birds (Nudds and Bryant 2000) and shorebirds unsuccessful
in gaining necessary fat reserves have very low survival rates (Brown et al. 2000b).
To better understand how management actions might reduce disturbance, I in-
vestigated recreational activity and the responses of birds (primarily shorebirds) on
a Southern California Beach. My research objectives were to determine: (1) factors
associated with bird and human use of the study site and (2) how disturbance varied
with bird species, human activity and the distance between the two. Based on similar
studies done with other species (Burger 1986), I expected that the effect of an activity
on birds would vary among activity types and that some bird species would be more
sensitive to disturbance than others (Burger and Gochfeld 1998).
People can disturb birds if they approach too closely or too quickly. In addition,
some dogs may actively chase birds for prolonged periods. The sensitivity of shore-
birds to dogs is illustrated by the observation that snowy plovers react at twice the
distance to dogs that they do to pedestrians (Fahy and Woodhouse 1995; Lafferty
2001). Perhaps this heightened reaction is because being chased conditions birds to
be wary of dogs or because birds instinctively view dogs as predators (Gabrielsen and
Smith 1995). Although they do not remove habitat or kill birds directly, disturbances
cause birds to suspend feeding and/or expend energy in ﬂight, movement or vigilance.
Impacts to birds are most likely a result of cumulative effects on reproduction and
survivorship. Birds that forage slowly or ineffectively may not build the requisite fat
reserves that are especially important to stressed and depleted migrants who must rest
and feed to successfully resume their migratory journey (Puttick 1979).
Studies on piping plovers indicate that reproductive success is lower in areas with
high human disturbance because of reduced foraging efﬁciency and the depletion
of fat reserves (Burger 1986, 1991, 1994). In areas where people are absent, piping
plovers can spend 90% of their active time feeding compared with less than 50% in
areas where people are common (Burger 1994). Disturbance can also cause birds to
abandon habitat (Burger 1986). On the northeast coast of North America, gulls and
terns are least likely to be permanently displaced, ducks usually move a short dis-
tance while herons, egrets and shorebirds are most likely to be displaced the furthest
distance (Burger 1981). In Ventura County, for example, shorebird abundance is low
on beaches with high human use, presumably because disturbance causes birds to
seek more isolated locations (McCrary and Pierson 2000). Pet activity, in particular,
reduces shorebird abundance (Burger 1981; Klein 1993) and those birds that remain
must spend more energy on vigilance and escape at the expense of foraging and rest
(Pﬁster et al. 1992; Burger 1993; Burger 1994).
For this study, I observed shorebirds and human activity on the beach. In par-
ticular, I noted whether activity disturbed birds. Shorebirds were disturbed very fre-
quently. The effect of disturbance was inﬂuenced by the type of activity and varied
among bird species. Effects of disturbance on shorebird feeding and distribution were
difﬁcult to determine.
Materials and methods
The study site (Figure 1) was a 2.85-km stretch of coastline that surrounds Coal Oil
Point between Ellwood Beach and the community of Isla Vista (Santa Barbara Coun-
Figure 1. Map of the transect and study area.
ty, California). This area has a rich high-intertidal invertebrate assemblage, presum-
ably due to the large amount of drift algae deposited on the beach from offshore kelp
forests (Dugan et al. 2000), and attracts a diverse and abundant shorebird community.
The Southern Pacific Coast Regional Shorebird Plan considers Coal Oil Point an
important area for shorebirds (Page and Schuford 2000).
With an assistant, I conducted weekly shoreline surveys from January 1999 to
January 2000 along the beach between 10 A.M.and2P.M. The survey transect was
established to cover a recent (1999) US Fish and Wildlife Service designation of
western snowy plover critical habitat. I divided the study area into 11 sectors based
on landmarks, property boundaries and existing transects. We noted the weather and
tide conditions at the start of the survey and collected beach proﬁle data at each sector.
For each sector, we counted the number of feeding and non-feeding birds (all species),
as well as other animals and humans using the beach. We only counted birds if they
interacted with the habitat. Usually, this meant that the bird was on the beach. We did
not count birds that ﬂew over-head with the exception of raptors which we counted
if they were in clear view of the beach (due to their potential to disturb). We moved
rapidly enough so that the chance of double counting was low. Nonetheless, it was
possible to record people or birds in more than one transect or to miss them entirely.
We also recorded disturbances that clearly caused birds to ﬂy or move. We actively
avoided disturbing birds and when birds reacted to us we did not record the event as a
disturbance. Disturbance agents were classiﬁed according to type, behavior, distance
from bird(s) and location on the beach. Disturbed birds were classiﬁed according to
species, behavior prior to disturbance, number of birds and response. Survey dates
alternated between weekends and weekdays.
Depending on the comparison made, I analyzed data using Pearson’s or Spear-
man correlation coefﬁcients, Fisher’s exact test, Kruskal–Wallis, Multivariate repeat-
ed measures analysis of covariance (ANCOVA) and χ22×2 contingency tables
when the data met the assumptions of the test employed. Counts were standardized
for sector length prior to analysis. All data were correlational so associations do not
necessarily imply causal relationships among variables.
13 881 birds representing 57 species were counted during 48 surveys. Figure 2 lists
the species and shows the frequency and abundance of the most common species. Half
of the birds observed were feeding. The western snowy plover, a federally threatened
bird, was the most abundant species and represented 25% of the birds seen.
Bird abundances and density (Figure 2, Table 1) varied among seasons according
to migration patterns, but did not vary significantly from weekend to weekday. Bird
density also decreased marginally with tidal height and varied significantly, but incon-
sistently with temperature (Table 1). The density of birds varied significantly among
sectors along the transect (Figure 3, Table 1). The birds were attracted to areas with
exposed, rocky substrate (areas G–K, see Figures 1 and 3, had exposed rocks on some
days; at these sites, the relative abundance of birds was positively associated with the
percent of the beach proﬁle that was exposed rock, r=0.61, n=231, P<0.01).
The proportion of rock substrate in these sectors was higher in the winter (due to sand
removal by winter storms) and at low tide. Snowy plovers were not seen in the ﬁve
sectors closest to the town of Isla Vista. Proximity to Isla Vista associated positively
with crow (r=0.82, n=10, P<0.05) and western gull abundance (r=0.71,
n=10, P<0.05). There were no indications that human activity reduced bird
abundance at the scale of a sector. For example, the relative abundance of birds in a
particular sector (i.e., the extent to which bird density deviated from the mean density
at that sector) was not negatively associated with the amount of human activity in a
sector (average r=0.09, n=10, P>0.05).
During the average observation period there were 51 people along the transect
(18 per kilometer). The average (and standard deviation) counts over the 48 dates
were 31.8 (29.8) people walking or jogging,18.9 (25.0) sitting, 4.8 (4.4) dogs and
0.2 (0.9) horses. Other potential disturbance agents included 7.6 (8.7) crows and 0.2
(0.5) raptors. People were evenly distributed throughout the transect except for a high
Figure 2. Frequency and abundance of common bird species. Species abbreviations (from the English) as
per Klimkiewicz and Robbins (1978) listed below by feeding guild. Common shorebirds were: whimbrel
(WHIM), western snowy plover (SNPL), willet (WILL), sanderling (SAND), marbled godwit (MAGO),
semipalmated plover (SEPL), black-bellied plover (BBPL), western sandpiper (WESA), greater yellowlegs
(GRYE), American pipit (AMPI), least sandpiper (LESA), black turnstone (BLTU), long-billed curlew
(LOCU), killdeer (KILL), and dunlin (DUNL). Shorebirds seen but not plotted were: surfbird, spotted
sandpiper, ruddy turnstone, long-billed dowitcher, American avocet and wandering tattler. Common gulls
and terns were: western gull (WEGU), Heerman’s gull (HEEG), California gull (CAGU), ring-billed gull
(RBGU), royal tern (ROTE), mew gull (MEGU), and Bonaparte’s gull (BOGU). Gulls and terns seen but
not plotted were: least tern, Forster’s tern and Caspian tern. Common ‘Misc piscivores’ were: snowy egret
(SNEG), great egret (GREG), double-crested cormorant (DCCO). Misc. piscivores seen but not plotted
were: brown pelican, green heron, common merganser and great blue heron. Common land birds were:
American crow (AMCR), American pipit (AMPI), Say’s phoebe (SAPH), barn swallow (BASW), cliff
swallow (CLSW), American kestrel (AMKE), turkey vulture (TUVU). Land birds seen but not plotted
were: white-tailed kite, merlin, western kingbird, loggerhead shrike, European starling, white-crowned
sparrow, Cooper’s hawk, red-shouldered hawk, and violet green swallow. Waterfowl seen but not plotted
were: Canada goose and brant.
Table 1. Multivariate repeated measures analysis of bird density. Sectors,
not dates, were used as repeated measures since the same tide, temperature,
season and weekend designation affected all sectors within a given date.
Source Wilk’s λF df P
Sector 0.38 4.41 10, 27 0.0010
Season 0.11 2.89 30, 79 0.0001
Weekend 0.59 1.86 10, 27 0.0975
Season ∗weekend 0.14 2.59 30, 79 0.0004
Temperature 0.37 4.65 10, 27 0.0007
Tide 0.55 2.20 10, 27 0.0505
Figure 3. Beach width, substrate type and density of birds and humans along the transect.
density at a sunbathing area in the middle of the transect (F) and a low density at the
most eastern sector (K, east of the Camino Majorca Stairs) which was often narrow
or covered by water (Figure 3). Not surprisingly, human activity (Figure 4, Table 2)
was substantially higher on weekends.
Figure 4. Seasonal variation in beach use by humans and birds (includes all bird species). Sample size
included in bar or next to point. Weekend effect for birds removed for simplicity. Error bars indicate 95%
conﬁdence intervals. Averages were based on a weekly 2.85 km beach transect. See Tables 1 and 2.
Table 2. Multivariate repeated measures analysis of human
density. See Table 1.
Source Wilk’s λF df P
Sector 0.84 0.51 10, 27 0.8675
Season 0.47 0.78 30, 79 0.7796
Weekend 0.46 3.13 10, 27 0.0088
Season ∗weekend 0.47 0.79 30, 79 0.7676
Temperature 0.82 0.59 10, 27 0.8014
Tide 0.88 0.94 10, 27 0.9427
During the 2–10 min we observed them, 10% the people disturbed an average of
10 birds each (of which about 7 ﬂew). Joggers, which were less abundant than walk-
ers, had the same probability of disturbing birds but disturbed twice as many birds per
disturbing person (Table 3). Walkers, on the other hand, were more often in groups
so that there was, on average, no difference between the number of birds disturbed
by a walking event or a jogging event. People not moving along the beach were much
less likely to disturb birds and, when they did, they disturbed far fewer birds. Most
disturbances occurred when a disturber was within 20 m of a bird (Figure 5).
On average, there were 11 dogs to every 100 people, for an average density of
2 dogs per km. Due to the increased amount of human activity on the weekends, dog
abundance was more than twice as high on weekends (8) as on weekdays (3) (t-test,
P<0.005). Thirty-nine percent of dogs observed disturbed 22 birds each, 75% of
which ﬂew (Table 4). Leashing reduced both the probability that a dog disturbed birds
(2 ×2χ2=5.1, Fisher’s exact test, (1 tailed) P=0.018) and the number of birds
per disturbance (Table 4). However, only 7% of pets were leashed. About 9% of dogs
chased birds during the brief observation period. Not surprisingly, dogs that chased
Table 3. Disturbance to shorebirds by people. Disturbance was deﬁned as causing a bird to move or ﬂy.
Activity corresponds to the total counts described as means in the Results. ‘% that disturb’ was based
on a 2–10 min observation period and was thus an underestimate of what a person disturbed during their
entire time on the beach. Disturbers were divided into walkers, joggers and bike riders. A disturbance
event could be caused by more than one disturber, e.g., two joggers, so data were divided accordingly.
‘Birds/disturbance’ was the number of birds disturbed per event. ‘Birds/disturber’ was the number of
birds disturbed per human that was involved in a disturbance. Standard deviations were not calculated
for the latter because of the difﬁculty in assigning disturbed birds to individuals in a group of disturbers.
Aircraft were present, but were not recorded. They did not cause disturbances in this study.
Walk Jog Still/Play Bike Total
Activity (n) 1524 907 – 2431
Disturbed (%) 16 0.4 – 10
No of events, No of disturbers 128, 201 109, 127 4, 7 8, 11 259, 346
No of disturbed birds 2272 3160 16 104 5552
Birds/disturbance (SD) 17.8 (27.3) 29.0 (63.8) 4 (5.3) 13 (4.8) 22 (46.7)
Birds disturbed/disturber 11.3 24.9 2.2 9.4 16
Disturbed birds that ﬂew (%) 62 84 81 88 74
Figure 5. Relative frequency distribution of distances between birds that were disturbed and the disturbing
agent. Each disturbance type sums to one. See Tables 3 and 4 for the relative abundance of the disturbance
birds were significantly more likely to disturb birds than were unleashed dogs that
did not chase birds (2 ×2χ2=41, P<0.0001). Although dogs that chased birds
disturbed a greater number of birds per event than unleashed dogs that did not chase,
this difference was not statistically significant.
There was substantial variation among bird species in the proportion of individ-
uals that were disturbed (Figure 6). Neither size of bird, guild (e.g., gull, shorebird,
piscivore), frequency of occurrence or density had an effect on the proportion of
individuals of a particular species that was disturbed (Multiple regression with all
P>0.05). A smaller proportion of land birds (10%) was disturbed than other birds
(59%) (n1=33 of the most common species, Mann–Whitney U=143, P=0.022).
Although a higher proportion of aquatic bird species that frequented the water’s edge
Table 4. Disturbance to shorebirds by dogs. See Table 3 for explanation. All chasing
dogs were unleashed but were not included in the unleashed totals.
Leashed Unleashed Chasing Total
Activity (total n, see Table 3) 18 221 25 264
Disturbed (%) 11 34 100 39
No. of events, No. of disturbers 2, 2 61, 75 25, 25 88, 102
No. of disturbed birds 11 1329 727 2229
Birds/disturbance (SD) 5.5 (6.3) 22.5 (40.9) 29.1 (38.8) 24.2 (39.2)
Birds/disturber 5.5 18.3 29.1 21.9
Disturbed birds that ﬂew (%) 100 76 81 72
Figure 6. Variation in disturbance among the most common aquatic birds. Data were pooled over all survey
dates. Bars are 95% conﬁdence intervals around the percentage for the pooled data. Abbreviations as per
were disturbed (78%) than aquatic birds that were more typically found on the dry
sand (19%), this was not significantly different, perhaps due to low sample size
(n2=26 of the most common aquatic species, Mann–Whitney U=29.5, P=0.08).
There was a non-random distribution of the locations (dry sand, moist sand, saturated
sand or rock, χ2=6032, df = 3, P<0.0001) of disturbances (number of disturbed
birds) indicating that disturbances were concentrated in moist and saturated sand
(Figure 7). The same pattern was evident for disturbance events and disturbers. These
results were likely due to the easily observable pattern that more humans and birds
(except snowy plovers) were on the lower beach (though these data were not specifi-
cally taken for humans unless a disturbance occurred).
The proportion of birds disturbed increased with the amount of activity in each
beach sector (Spearman ρ=0.41, n=366, P<0.01). The average distance that
birds reacted to humans increased with the proportion of birds that were disturbed
on a particular day (r=0.49, n=37, P<0.01), suggesting disturbance sensi-
tized birds. In contrast, the distance that birds reacted to dogs was independent of
the amount of disturbance on a particular date (r=−0.03, n=37, P>0.05). The
proportion of all birds feeding did not decline significantly with increased disturbance
rates (r=−0.18, n=45, P>0.05) or with increased beach activity (r=−0.14,
n=45, P>0.05), although for some common bird species (black-bellied plov-
er, r=−0.47, n=27 and willet, r=−0.42, n=21) the association between
disturbance and feeding was stronger.
Figure 7. Location of disturbances among substrate type (observed) relative to available substrate type
(expected). Expected values for each substrate type are the total number of disturbed birds times
the proportion of a particular substrate type recorded for the beach (averaged over all dates). Peo-
ple and birds were generally lower on the beach (moist and saturated), with the exception of a sunbathing
area, where most of the people were on the dry sand. The departure from expected, therefore, is most
likely because people and birds did not use the habitat evenly (because we did not record habitat use,
I could not evaluate this quantitatively).
When averaged over the course of the year, there was no association between the
spatial distribution of birds and the spatial distribution of people along the transect
(r=0.12, n=11, P>0.05). Although disturbed birds always moved away from
the activity that disturbed them (see also Smit and Visser 1993), an analysis of the
distribution of birds among sectors and dates did not reveal that birds increasingly
occupied less populated sectors as overall beach activity increased (r=0.0, n=45,
P>0.05), a trend that was consistent for all common species. This was true for
an independent study of snowy plovers which found that plovers did not ﬁnd more
isolated locations to roost as human activity increased from the early morning to the
afternoon (Lafferty 2001).
Large-scale seasonal variation and habitat features such as a lagoon and rocky inter-
tidal area determined the distribution of birds at Coal Oil Point. Work/school sched-
ules inﬂuenced patterns of human activity within the study area. Although people
disturbed birds, their presence did not significantly alter the large-scale distribution of
birds. Disturbances were frequent and varied according to the type of human activity.
Birds were particularly sensitive to dogs. Most disturbances occurred on the wet sand,
the area where many birds fed and humans walked and jogged.
At Coal Oil Point, a lagoon mouth (Devereux Slough) in the center of the transect
(sector E) attracted birds around its margin (and snowy plovers that roosted on the
dry sand of the delta) and a rocky point provided rich foraging habitat at low tide for
many species, especially in the winter where rocks were exposed. Crows and western
gulls may have been more common near the college student community of Isla Vista
because these species will feed on garbage (Ward and Low 1997). The change in
sector use with season by birds was most likely due to the fact that rock was more
exposed at the eastern sectors in the winter and due to the lower abundance of snowy
plovers (the species with the highest site ﬁdelity to the lagoon mouth) in the summer
The weekday–weekend effect was the main factor determining human density.
Unfortunately, due to the several day spaces between counts, I could not determine
whether bird densities along the transect actually declined in response to weekend
activity. In comparison to birds, spatial variation in how people used the site was
relatively low except for high numbers of people sunbathing at a sector called Sands
Beach, particularly on weekends (the spatial distribution of people in the water was
strongly inﬂuenced by two surfing areas – we did not count surfers if they were in
the water). Although one might expect summer beach crowds, winter months had as
much activity, presumably due to good winter surfing conditions, overcast summer
weather and the fact that many students were away during summer break.
The lack of an association between the spatial distribution of birds and the spa-
tial distribution of people along the transect suggests that habitat features may be
more important in determining the distribution of birds than human activity, at least
at the spatial scale at which I divided the transects into sectors. When disturbed birds
moved, they did not often move out of the sector where they were disturbed, making
the effect of disturbance on displacement difﬁcult to detect on the scale of a sector.
This is consistent with McCrary and Pierson (2000) who did not see an effect of
human activity on shorebird abundance when they limited their analysis to a partic-
ular beach; only when they compared human and bird use among beaches did they
see a negative association. Burger (1986) also saw an effect of disturbance on bird
distribution when comparing sites at large spatial scales.
Fitness impacts to birds from single acts of disturbance are difﬁcult to assess (Burger
1986), except for nesting birds, which may suffer dramatically from a single event.
Along this stretch of beach it was clear that each bird was disturbed, on average,
dozens of times per day. Such disturbances may come at the expense of feeding and
rest for species that are making energetically demanding migrations (Nudds and Bry-
ant 2000). The lack of an association between feeding (for most birds) and human
activity contrasts with the results of Burger and Gochfeld (1991) who found that hu-
man activity altered foraging rates of sanderlings, underscoring that species specific
differences (as seen in this study) may be important in this regard (Burger and Goch-
feld 1998). That birds reacted to humans at a greater distance on days where the risk
of getting disturbed was high suggests that birds can be hypersensitized to humans.
It is also interesting that birds changed their sensitivity to humans but not to dogs,
perhaps because being chased always gives birds a valid concern about the presence
of dogs. These data differ from Fitzpatrick and Bouchez’ (1998) observation that
shorebirds can become habituated to disturbance. This might be because habituation
may require predictable patterns of human activity which birds can learn pose no
threat to them (Burger 1989; Burger and Gochfeld 1991). At Coal Oil Point, human
activity is neither predictable nor inconsequential for birds. Other factors shown to
increase sensitivity of birds, but not investigated here, include time of day (Burger
and Gochfeld 1991), watercraft (Burger 1998), noise levels (Burger and Gochfeld
1998) and location to location variation (Burger 1986; McCrary and Pierson 2000).
Dogs disturbed birds disproportionate to their numbers due to the tendency for
some dogs to chase birds and the possibility that some birds, such as snowy plovers,
are more sensitive to dogs than humans (Lafferty 2001). The observation of 11 dogs
to every 100 people was slightly less than the 15 dogs per 100 people observed at 13
Ventura County beaches (40 miles south of the study), where three beaches had over
30 dogs per 100 people (McCrary and Pierson 2000). Although the countywide leash
law was posted at the main beach entrance, this law was not enforced, explaining the
near absence of compliance by dog owners.
The differential susceptibility among bird species to disturbance was partially ex-
plained by habitat use. Most disturbances occurred at the lower beach where many
birds were foraging or resting and many people were walking or jogging. Birds that
tended to roost (snowy plovers) or forage (whimbrel) in the upper beach were less
frequently disturbed. This is best explained by the likelihood of a disturbance greatly
increasing as the distance between the disturber and the bird decreases. Fitzpatrick
and Bouchez (1998); Burger (1981) also note that different species responded differ-
entially to disturbances. Fitzpatrick and Bouchez (1998) suggest that this relates to
differences among species in cryptic plumage. Although it is not clear that plumage
explains most of the variation seen in my study, such a pattern is consistent with the
observation that snowy plovers rely on cryptic coloration and remaining motionless to
avoid predators and were much more hesitant to ﬂy (25%) from a disturbance relative
to other species (75%).
Given the high rates of disturbance and the resulting implications for shorebird con-
servation, what actions could reduce impacts? The main ﬁnding from this study is
that the rate of disturbance at a particular location was primarily a function of: (1) the
type, location and frequency of human activity and (2) the distribution, abundance
and species composition of the bird community. Managing any of these factors could,
therefore, reduce disturbance rates. One goal might be to minimize overlap between
birds and humans by concentrating human activity away from preferred shorebird
habitat (such as lagoon and rocky intertidal areas). Possible management actions to
accomplish this might include the strategic distribution of parking lots and beach-
access points. Where birds and humans do overlap, reducing the frequency of high-
impact activity, such as unleashed pets, could also substantially reduce disturbance.
Changing human behavior is likely to be a challenge, requiring sustained efforts of
education, notiﬁcation and enforcement.
Although little is presently done specifically to protect shorebirds, the guiding
land-use document for coastal California, The California Coastal Act, acknowledges
the need to ‘regulate the time, place and manner of public access’ to protect the ‘fra-
gility of the natural resources in the area’ (California Public Resources Code Section
30214(a3)). This goal is consistent with the Southern Pacific Coast Regional Shore-
bird Plan that proposes limiting human disturbance to shorebirds and, in particular,
restricting dogs from beaches with important shorebird habitat and leashing dogs
on all other beaches (Page and Shuford 2000). As conﬂicts between wildlife and
human recreation become more acute, coastal policy, planning and implementation
may beneﬁt from studies such as this.
Special thanks to Darcie Goodman, Nick Kalodimos, Kathleen Whitney and sever-
al volunteers for participation in surveys. Jenny Dugan, Dave Hubbard, Jack Mel-
lor and Kathleen Whitney provided helpful comments. Nick Kalodimos helped with
manuscript preparation. The Coal Oil Point Reserve of the University of California
provided access and support.
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