Thursday, May 5, 2011
To some brown pelicans are magical, to some they're pooping pests. But this spring there are a heck of a lot of them flying up and down the San Diego coast.
MAUREEN CAVANAUGH: To some they're magical, to some they're pooping pests. But everyone can agree that there are a heck of a lot of pelicans this spring along the San Diego coast. The population of brown pelicans is bigger than usual and they've arrived in Southern California a lot earlier than usual. Natural scientists say they don't really know why.
GUESTS: Phil Unitt, curator of the Department of Birds and Mammals, San Diego Natural History Museum
Chris Redfern, president, San Diego Audubon Society
CAVANAUGH: I'm Maureen Cavanaugh, you're listening to These Days on KPBS. To some, they're magical, to some, they are pooping pests of but even can agree there's a heck of a lot of pelicans this Spring along the San Diego coast. The population of brown pelicans is bigger than usual, and they've arrived in Southern California a lot earlier than usual. Natural scientists say they don't really know why. I'd like to introduce my guests, Phil unit is curator of the department of birds and mammals at the San Diego natural history museum. Phil, good morning.
UNITT: Good morning.
CAVANAUGH: And Chris red fern is president of the San Diego Autobahn society. Hi Chris.
REDFERN: Hi, Maureen.
CAVANAUGH: Why don't we open up our phones a little bit? If you've been seeing these pelicans around and want to tell us about, it's 1-888-895-5727. So Chris, when we say there are a lot of pelicans flying around the coast, what are we talking about? How many pelicans? How often are they seen?
REDFERN: Well, it's interesting. We have a fund raiser every spring called a birdathon where we have teams go out, and look for different species of birds on a given day, so I've been out along the coastline quite a bit this month, this past month, and I've certainly noticed that there are larger groups of brown pelicans flying over head in their beautiful, you know, lines or V formations. So while we don't have specific numbers about how many more there are, there's definitely a feeling that we're seeing, you know, more pelicans than we would normally see this particular time of year. So it's been really fun.
CAVANAUGH: And is the San Diego natural history museum, Phil, getting calls about this?
UNITT: We've been getting calls from the media.
MAUREEN CAVANAUGH: Ah, ha. Because the media as well as other people have been saying why are there so many birds up there? Do we have request idea of why they are here so early?
UNITT: Sea birds especially the brown pelican shift around with the food supply. And it may not be good news for the pelican as a species that they're here in large numbers at this time of year because now in the spring is when they should be nesting. And if they're experiencing a failure of their nesting, then they may leave the colonies and come where the fish are. And if the fish happen to be off the San Diego coast, then that may be why they're here.
CAVANAUGH: Chris, where do they usually nest?
REDFERN: They're usually nesting on off shore islands south of here.
CAVANAUGH: South of here.
REDFERN: Yeah, and also along the Coronados on islands are the nearest locations.
CAVANAUGH: And when do they usually get here in any numbers?
REDFERN: Well, you see them peek in the early summer months like June and July.
MAUREEN CAVANAUGH: So they're really early this year.
UNITT: Of course we see some all year-round since there's an important colony on los Coronados islands, it's just a few empties for them to fly back and forth between San Diego and the islands.
CAVANAUGH: What would make them leave their nests and come here for food? I mean, do they just all of a sudden get very hungry, Phil?
UNITT: Yes. The distribution of fish is highly variable. And the numbers of various species fluctuate from year to year and from season to season with changes in the upwelling and oceanographic conditions, and it's quite common for many species of sea birds to have a failure of their breeding colonies if the fish move away and the middle of the breeding season. The eggs or chicks may be abandoned and starve.
MAUREEN CAVANAUGH: Ah, so that may be what's happening this year.
UNITT: It may be. I don't know.
CAVANAUGH: Do we have any idea, Chris, what the pelican population is usually like that winds up here in San Diego in the late summer?
REDFERN: Phil? What do you think?
UNITT: The figures that I saw in the report of the U.S. fish and wildlife service when it removed the brown pelican from the endangered species list in 2009 was that the nesting population in what they call the Southern California bite, which goes from the channel islands to northern Baja, was about 11700 pairs of now, those would shift over a large area, in fact, then in the late summer, many of them would move out of our area entirely. But if you look at the region of the whole, those are the figures I've seen.
CAVANAUGH: I'm speaking with Phil unit, he's cure indicator of the department of birds and mammals at San Diego natural history museum, and Chris red fern, president of the San Diego Autobahn society. Phil, you mentioned that the brown Mel can was endangered. The population has snapped back dramatically. Tell us a little bit about that history. Why was this an endangered species?
UNITT: In the 1940s, 1950s with the production and use of the pesticide DDT, it washed into the ocean, it accumulated through the food chain so that animals at the top of the food chain such as the brown pelican, the peregrine falcon, are the bald eagle, the osprey, had high concentrations. That DDT disrupted the female's calcium cat blimp. So they laid eggs whose which he wills were too thin, and they were crushed when they were incubated. And so the production of young was extremely low to none for quite a few years and the population crashed. Ultimately DDT was banned, at least for use in the United States , and the population recovered primarily in the 1980s is when we really saw a big increase in pelicans, and I got a lot of calls at the museum from the public then about increasing numbers of pelicans.
MAUREEN CAVANAUGH: So Chris what we're actually seeing in the skies over San Diego is something of a success story.
UNITT: That's right.
REDFERN: That's and that's what I wanted to bring out in what Phil was just saying is that all of the species that he just talked about, the peregrine falcon, the bald eagle, the brown pelican, all were listed as endangered under the endangered species act, and all are endangered species act success stories. A lot of people feel that the protection and recovery of endangered species is kind of a expensive, difficult, and complicated and often unsuccessful activity. But in fact, it is a very successful activity, and it's one of the most important protectors of biodiversity that we have in the United States, the endangered species act.
CAVANAUGH: In fact, I know that you're working on a particularly endangered species, a bird species called the lease turn here in San Diego. Before we get to what you're doing with that, that species of bird, tell us a lot bit about the bird. Where does it live and why is it important? And I'll go to you Chris first, and maybe Phil, you can chime in on that as well.
REDFERN: Yeah, so the California lease turn is a subspecies, and it comes to San Diego in the summer time to breed. And in fact I was just talking to the biologists who monitor some of the breeding colonies here in San Diego County, and they just arrived right now, and they seem to be enjoying the warm weather we've been having, and they've come up from the south, and they start to billed their nests which are small scrapes in the sand. And they will eventually line those scrapes in the sand with shells, and begin their beautiful courtship rituals of the males going off, finding fish, and then coming back and trying to woo females by showing what great providers they are. And they're a beautiful species, they're a very small turn. Turns -- most turns are diving feeders, so they dive in shallow water for small fish. And they have the -- the lease turn is the smallest of the turns that we see here. It has a long forked tail, black cap, just a beautiful little graceful acrobatic bird.
CAVANAUGH: Phil is this -- is the lease turn, what is its status today? Is it a healthy population of birds?
UNITT: The population has increased in the early 1970s when it was first listed as endangered, this was only maybe 300 or so in the whole State of California. And now the population has risen to between about 6 and 7000. And about 60 percent of that is here in San Diego County.
CAVANAUGH: Oh, wow.
UNITT: So we're very important to the survival of the lease turn in the whole state.
CAVANAUGH: I know that the Autobahn society here, Chris, your group is doing something about a nesting site for lease turns here.
REDFERN: Yes. There are 17 nesting sites in the county that are used by the lease turns, and they're actively managed and monitored throughout the summer. We have been involved in a number of those sites, primarily in Mission Bay park, there's a site called mariner's point that we've been actively helping to manage and protect for over ten years. And we use groups of volunteers, and it's really for us a way to get people out in nature as Richard Louv was talking earlier in the show about having that affiliation with other species. We're providing that opportunity to allow the members of the public to participate in helping to prepare these nesting sites by removing vegetation. They like a certain amount of vegetation so they can see predators, most of the predators are other birds so they like an open area where they can see for a far distance. And so we involve folks in doing that, and it's a great way for them to learn about endangered species and to kind of connect to the urban wildlife that, you know, as Richard was saying, we have a city here that is full of endangered species, which is quite unique, and so getting people involved and helping to protect and support them here is part of what we do.
MAUREEN CAVANAUGH: You know, sometimes, Chris, endangered species with funny names are sort of a punch line. People don't take them as seriously as perhaps they should. So tell us why we should care about these species issue the les turn, and these other birds that we hear with who are endangered.
REDFERN: Oh, gosh, Maureen, to me it's a very personal thing. I think that life is richer when there's a diversity of life to explore and understand and interact with. We all know that in different parts of the world we find that areas in high biodiversity can be great resources for production of pharmaceuticals and all these other things so there's that aspect too. But I think on a very basic level we all need to understand that the natural world supports us. That is the natural infrastructure that supports all life, and for us to respect all life and give all life an equal chance at surviving, I think is an ethic work promoting and something that I personally feel very passionate about.
CAVANAUGH: And Phil?
UNITT: Wouldn't it be the height of arrogance for our generation to kill off species to deprive future generations of whatever value they would get from that component of our ecosystem?
CAVANAUGH: So even if we can't say, well, we get this pharmaceutical from this bird and we get this and that and the other thing, it's just the actual principle of the matter. What right do we have? And if we can maintain this species and make sure and bring back the population, that's a sacred trust. Is that your point?
UNITT: And what future uses at any kind of level are future generations going to have? We can't even imagine, you know, just think that it was only in 1953 that DNA was even understood. And now DNA can be extracted from specimens of extinct birds that went extinct even before DNA was discovered.
THE COURT: Right. Yeah.
UNITT: So it's just very arrogant and narrow minded for people to think that we know everything there is to be known about nature now.
MAUREEN CAVANAUGH: Well, apparently we're doing at least right by the lease turn at this point. And also -- and we're experiencing the joy of this population pelican explosion.
CAVANAUGH: So I want to thank you both, Phil unit and Chris red fern. Thanks so much for speaking with us today.
REDFERN: My pleasure.
UNITT: Thank you Maureen.
MAUREEN CAVANAUGH: If you would like to comment, please go on-line, KPBS.org/These Days. And stay with us for hour two of These Days, coming up in just a few minutes here on KPBS.