Long-Term Monitoring Program and Experiential Training for
Students (LiMPETS): Monitoring the Sanctuary’s Rocky Intertidal
with High School Students and Other Volunteers

The intertidal zone is the coastal strip that is covered and uncovered by the sea during the rise and fall of the tides. An incredible variety of life inhabits this zone, and the rocky intertidal of central California is especially rich. There are the familiar fishes, snails, mussels, crabs, and sea stars as well as beautiful nudibranchs and sea anemones, delicate hydroids and bryozoans, and colorful sponges and ascidians that abound in crevices and pools. Bright green surfgrasses mark the lower parts of the low tide zone, while bizarre forms of red and brown algae cover much of the middle and high zones. There are few places in the world where so many kinds of organism live in such a small area. Abundant oxygen, nutrients, and wave motion make this area one of the richest and most productive on earth.

Figure 1. Abundance of California sea mussels (Mytilus californianus) within a 9 x 30 m permanent plot in the mid zone at the Natural Bridges site. Values for 1973 to 1997 taken by UCSC undergraduate students; those of 2000 and 2001 taken by Aptos High School students. Numbers indicate number of quadrats counted.

Indeed, the intertidal zone is a wonderful place to learn about life on our planet. For many years biologists have recognized the opportunities for understanding nature by studying the intertidal, and many of our ideas about how communities of plants and animals function come from observations and experiments done there. The organisms are arranged in bands, with fewer species higher up in the intertidal and the most species crowded in the low zone. This gradient is similar to what one would see by traveling over great distances from mountain tops to lowlands, deserts to wetlands, or the polar regions to the tropics, and for the same reasons – but in the intertidal there are only a few meters to traverse and it is easily accessible. In more physically stressed regions, such as the high zone of the intertidal, species diversity is restricted to those few that can tolerate stresses such as temperature extremes and long periods without water. In contrast, in the more favorable regions, like the low zone of the intertidal, many species crowd together, vying for space and competing intensely to survive. Though the intertidal appears benign on an early morning low tide, the low zone is a place of high conflict, full of predators and competitors using nearly unimaginable means for offense and defense.

Figure 2. Abundance of California sea mussels (Mytilus californianus) along the vertical transect (across the intertidal from high to low) at the Natural Bridges site, as counted by professional researchers in the PISCO program and Aptos High School students. Each quadrat along the transect was counted by two professional teams and two student teams.

The accessibility of the rich and varied biota in the intertidal and the information accumulated from years of study there provide a wonderful opportunity for the public in general, and curious youngsters in particular, to learn about biology and the natural world. Programs developed by the national marine sanctuaries and public aquariums, such as the Monterey Bay Aquarium, have been leading the way in introducing the intertidal to people from all walks of life. Interpretative materials in the form of written articles and books, videos, and web sites are proliferating to meet the increased interest, and these are leading to increased conservation efforts.

Watsonville High School students with their teacher, Burnne Yew, at the Point Pinos site. photo Christy Roe/Dawn Osborn

On the other hand, the very accessibility of the intertidal has led to more and more people visiting it. And while reckless collecting might be decreasing in response to better understanding and enforcement, simply clambering around on the rocks may disturb some species, leading to unpredictable changes. Moreover, by its very nature, the intertidal zone is a place exposed to many of the pollutants produced by human society. Contaminants released into the air fall on the surface of the sea, and those dumped on the land are washed into the sea. In addition, many contaminants that are discharged directly into the sea pass through the intertidal, and some of the material from all these sources is washed back onto the shore, ending up in the intertidal. Indeed, the animals and plants of the intertidal may be affected more severely by human activities than those in most other parts of the sea. Fortunately, because of their accessibility, they may also be the easiest to monitor and so can serve as our marine canaries.

For example, the tightly organized zonation pattern of the intertidal, with species sorted into bands with respect to tidal height, may be particularly sensitive to global warming because a rise in sea temperature leads to a rise in sea level. Such a rise in sea level should not only shift the entire zone higher on the shore but also change the zonation pattern. Moreover, we should expect the distribution of species along our coast to shift in response to a rise in both air and sea temperatures. At any given site, southern species would be expected to become more common and northern species less common. Indeed, that was exactly the result seen when species abundance was compared between the early 1930s and the mid 1990s at a site at Stanford University’s Hopkins Marine Station in Monterey Bay: several common southern Californian species that were rare or absent in the 1930s are now abundant there. But will all these predictions hold in general?

The biotic diversity combined with abundance, organization, and sensitivity to environmental change therefore present an enormous opportunity both for informing the public about life in the sea and for monitoring biotic changes over time. In particular, the education of high school students and other curious people can be enhanced while they collect important data to be archived and used to detect change. This is the goal of Long-term Monitoring Program and Experiential Training for Students (LiMPETS), which is being developed by the West Coast marine sanctuaries.

The rocky intertidal portion of LiMPETS* was developed at the Long Marine Laboratory of the University of California Santa Cruz (UCSC), with support from the California Sea Grant College program. Eight sites were developed in the Monterey Bay National Marine Sanctuary; five of these have already been used by six school groups and one volunteer group (see table, above). Three other sites have been developed and are open for “adoption.” At all the sites, half meter by half meter square quadrats are placed along a vertical transect – crossing the intertidal from the top of the high zone into the low zone, and marked with stainless steel eyebolts – and the abundance of selected algae and invertebrates are counted within them. Large animals that are infrequently found in the quadrats, such as owl limpets and sea stars, are counted and measured in larger, delineated areas that can be carefully searched. In addition, at four sites in Santa Cruz County where the intertidal is relatively uniform and covered predominately by a single species (mussels or surfgrass), large permanent plots have been established, and selected species are counted in randomly placed quadrats that permit statistical comparisons. Data collected by UCSC college classes are already available for those sites, going back to the early 1970s, for comparison (see Figure 1, p. 7).

Although getting high school students into the intertidal may be a great educational experience, it has been questioned whether they are able to collect reliable data. To make sure that they can, common species of ecological importance were selected for monitoring and their suitability tested by students in the field. Those that are difficult to distinguish (even by professionals) were either eliminated or combined into general groups. Moreover, protocols used in professional monitoring programs were followed, and data collected by students were found to be indistinguishable from those collected in the same quadrats by teams of professional researchers (see Figure 2, p. 7). The sites, species, and protocols are all on the LiMPETS project web site (www.limpets.org).

John Pearse, Dawn Osborn, and Christy Roe
Joseph M. Long Marine Laboratory, University of California Santa Cruz
*The sandy beach portion of LiMPETS is being developed by the Gulf of the Farallones National Marine Sanctuary (www.sandcrabs.org), and a pelagic, offshore sampling
program is planned by the Cordell Bank National Marine Sanctuary.

Are We Loving Our Tidepools to Death? New Study Examines Relationship of Visitor Use and Marine Life Biodiversity at Point Pinos

Rocky intertidal zones with pinnacle outcroppings and tidepools support some of the most diverse marine plant and animal communities along the coast. These habitats have become increasingly popular for their educational, recreational, and scenic values and have become more frequently visited by school groups, tourists, and the general public. However, studies have shown that heavy visitor use can negatively affect the communities in these habitats through trampling, collecting, handling organisms, and simply turning rocks. Point Pinos, a prominent rocky headland of the Monterey Peninsula, is one of the most biologically diverse and picturesque habitats in the Monterey Bay National Marine Sanctuary. It is of particular interest because it is easily accessible. Con- cerns have arisen that the marine life at Point Pinos is being negatively affected by visitor overuse. Visitors frequently explore the Point Pinos shore. photo Courtesy of Scott Kimura A study initiated in 2001 is obtaining data to determine the extent and magnitude of the biological impacts associated with visitor use at Point Pinos. Sampling is also being done in adjacent areas with less visitor use, for comparison purposes. The biological surveys consist of inventories of key species selected for their ecological or numerical importance and susceptibility to visitor impacts. Sampling transects are established in the upper and lower intertidal zones in each study area. Tidepools close to public access points are also being sampled to determine whether there are any indications that tidepools at Point Pinos are less diverse than those in areas with less visitor use. In addition, species at higher risk of being illegally collected for food, such as owl limpets and abalone, are being studied to determine the status of their local populations. Tenera Environmental of San Luis Obispo, California is conducting the studies. The Point Pinos Tidepool Task Force Research Committee, a panel comprised of local scientists and citizens, commissioned the study. The David and Lucile Packard Foundation, City of Pacific Grove, and Monterey Bay National Marine Sanctuary are financing the study, with the funding being administered through the Monterey Bay Sanctuary Foundation. BAY NET, a volunteer group specializing in marine science education outreach, is conducting the visitor census surveys and tallying the types of visitor activity observed. The final report, due to be completed in the spring of 2003, will provide a scientific basis for guiding resource management at Point Pinos. Scott Kimura Tenera Environmental