Science Behind the Scenery: Tomales Bay Biodiversity Inventory and Partnership

Point Reyes National Seashore


[waves lapping on a shoreline]

[Ben Becker] Biodiversity is a short term for biological diversity. The main definition is: the number of different species—how many different types of animals or plants or fungi are in a system. Within each one of those species, there's genetic diversity. And then, we also have community diversity. And a biological community is made up of the groups of species that are within that community.


If you think about your lawn, or you think about an area that's just a cornfield, these are monocultures; there's just one species in there. And we have to apply pesticides to these areas. We have to go in there and remove the pests and we're always fighting weeds. You can see how easily these areas are invaded when they're just a monoculture.

But when we have a healthy, high biodiversity system, they're able to often fend off these invaders, these pests, and everything maintains themselves at equilibrium much better. By having more species in your environment, there are more species with different jobs—different nutrient recycling jobs, different decomposition jobs. Having high biodiversity in your system also improves the efficiency of that system to fix carbon, to cycle nutrients through the system, which are important for all the other forms of life.

Habitats are often the substrate that biodiversity is placed upon. So, different habitats...rocky habitats will host one type of community of biodiversity, you know, a particular assemblage of sea stars or algae. Whereas, the same habitat might have a completely different biodiversity assemblage. And different sandy habitats in different areas might have relatively similar biodiversity, but there might be some components of that biodiversity that are different.

[waves lapping on a shoreline]

One thing to consider when you think about biodiversity is our knowledge of biodiversity in the world is really quite limited. We probably, all together, know or have cataloged under two million species that occur in the world. And this is everywhere—this is rain forests, this is oceans, this is desert. A lot of scientists estimate that there are as many as 30 million species around the world.

[waves lapping on a shoreline]

Throughout the world, there are a lot of different reasons that we lose biodiversity. The main reason is usually habitat loss, but another big reason is invasive species. These are species from another system, from another part of the world, that are brought in. They're almost like weeds.

[waves lapping on a shoreline]

Along this bay, we are looking at the biodiversity within this bay, because there are several threats to this bay that we want to understand how to control these threats—threats like habitat loss. We might lose some of our biological communities if we lose some of our rocky habitats or some of our sandy habitats to development or to pollution. We can only understand how to control the threats and what the impacts of these threats are if we understand what the biological diversity is inside the bay.

[waves lapping on a shoreline]

What we're doing right now, we're doing an inventory so that we understand how many species are there and what their population levels are. So, we have groups of scientists that go out, look at particular group of organisms—algae or invertebrates or fishes—monitor in the field through different capturing techniques or different monitoring techniques, whether they're going out, collecting them, taking them back into the laboratory to identify some of these species that are very difficult to identify without a microscope. And they can look at what species are there. Also, the distribution of those species around the bay. And then, we can go back later and say: "Are these habitats changing?" "Has this habitat been affected by pollution?" "Has this habitat been affected by heavy fishing pressure?" "Has this been affected by an invasive species coming in from another environment that might be displacing our particular species?" So, we're basically quantifying the distribution and how many there are in a particular area, and then tracking that over time.

[waves lapping on a shoreline]

We have what we call all of these different taxonomic working groups. Some are working on algae, some on fishes, some on microscopic phytoplankton. Some people are working on birds, some on mammals, and all of them work in their own respective area to do this inventory

[waves lapping on a shoreline]

Often, researchers, when they're working in a system—if they're working on fishes or they're working on a particular type of habitat—they often work in relative isolation. They communicate with one another about what their findings are, but their data and their analyses are often separate. Here, we have a group, a large group of scientists, graduate students, and, also, community members and students, who are all working together on this project. They go out on their own to do their particular surveying and inventory, but they all do it in a similar manner, so computer, one database system. So, if we want to map biodiversity around the bay, or if we want to look for hotspots of invasive species, or these are the most biodiverse areas, or these are the areas that are threatened, we can look at the information from invertebrates, from algae, all the different types of habitats, all together.

[waves lapping on a shoreline]

This project is really a community project. So, what we've done is we've gone out to the community, to the scientific community, to the educational community, and, also, to the local environmental community, and, also, the agricultural community. And we've formed a group that is all interested in helping to catalog what the biodiversity is of this bay.

So, that's one of the beautiful parts of this project is we've got the algae people and the fish people and the habitat people all talking together, so that we can look for these trends in biodiversity, not just in one particular group, like fishes or invertebrates, but what's going on with all of the biodiversity in this part of the bay where there might be a high impact.

[waves lapping on a shoreline]

Biodiversity is really important for several reasons It's important to humans, in the way that we live our lives. Most of our foods are derived from natural sources. At least 25 or 30% of our medicines are derived from plants in the wild. Having a diverse system often fills up all of the little niches in the environment, making it more difficult for invasive species to come in, or making it less likely that populations are going to decline.

[waves lapping on a shoreline]


The third part of the ten-part Science Behind the Scenery documentary featuring Marine Biologist Ben Becker, Ph.D., talking about the NPS partnering with a variety of biologists and scientists to inventory the biodiverse species of life inhabiting Tomales Bay.


6 minutes, 20 seconds


Pacific Coast Science and Learning Center

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