Pollinator and predator - endangered species as pollinators; includes related articles on building structures to attract bees and organizations to protect pollinators

As I camp alone in a narrow canyon, waiting for a nocturnal pollinator to visit an endangered wildflower, I recite the names of threatened pollinators from around the world:

Golden-manteled saddle-backed tamarins, moss-forest blossom bats, little wood-stars, turquoise-throated pufflegs, dibblers, apricot-breasted sunbirds, Duvacel's geckos, mahogany gliders, Hooey possums, Marianas flying-foxes, crowned lemurs, purple-backed sun-beams, marvelous spatuletails, yellow-footed honeyguides, four-colored flower-peckers, Bishop's oo's, and Regent honeyeaters.

These sounds may be all I ever get to know of these critters. Many of these pollinators are known by just a few diligent zoologists who have had the fleeting luck to be in the right place at the right time. A number of these threatened species of pollinators -- some 82 mammals, 103 birds, and one reptile -- have dwindled to fewer than a thousand individuals.

Like the endangered wildflower I am babysitting this evening, little is known of these pollinators' life histories. We presume that they were effective pollinators of certain loosely coevolved blossoms, but some of them may merely be casual floral visitors. Or, perhaps, all we know is that one individual was once documented ducking its head into the blooms of a certain flower. Its behavior suggests it may be a legitimate pollinator. ("Legitimate" here distinguishes it from an animal that feeds on a plant's nectar or pollen without aiding in cross-pollination of the plant.)

Three nights ago, while suffering insomnia and a fever due either to flu or biophilia, I stayed up through the twilight hours counting how many of the vertebrate wildlife species in the 1994 Red List of Threatened Animals were likely to be pollinators. The 186 vertebrate species that I tallied are but needles in the haystack compared to the total number of pollinators on this planet -- some 100,000 invertebrate species are definitely involved in pollinating the 240,000 species of flowering plants. We are decades away from knowing with any confidence what percentage of these 100,000 invertebrate pollinators are imperiled. Instead, I had to focus on the 186 imperiled pollinating vertebrates. My late night calculation was that 15 to 18 percent of those potential pollinators are already of conservation concern.

I have been watching whipoorwills diving after hawkmoths, bats darting across the canyon, and micromoths landing on the flowers of the rare Kearney's blue star. As I reach to clamp mason jar over an insect crawling on the blue star's inflorescence, I hear a scream echoing off the canyon walls. Somewhere on the higher ridges behind my back, a female mountain lion is caterwauling, yowling her heart out. I clumsily screw the lid back on filled a glass jar. "Forty-five seconds of screaming, presumably puma," I write in my field journal at 8:54 p.m., in case I end up in the kill jar of Felis concolor.

While the relative rarity of carnivores such as cougars is well recognized, the worsening scarcity of pollinators has remained beyond the reach of our society's antennae. I can affirm, `This is the first cougar I've heard caterwauling in my quarter century of living in the Southwest." My wife can assert, "I've lived, in puma country my entire life, and only once, in Big bend did I ever see one." But who on his Earth (other than the chiroptophiles over at Bat Conservation International) has a visceral sense of pollinator scarcity? And yet, when Martin-Burd sorted out hundreds of case studies of low seed set in flowering plants, he attributed 62 percent of these reproductive shortfalls to pollinator scarcity. An off-hand comment by Burd may be even more telling: the very showiness of flowers might be an indication that good pollinators are hard to come by.

Big, fierce carnivores may be naturally rare. if so, the last century's declines in seldom-seen nectar-feeding vertebrates may be even scarier than those that meat-eaters have suffered. A roost site in the Philippines once housed hundreds of thousands of flying-foxes; today you can witness a few hundred on the best of nights. The Panay giant fruit bat is altogether gone from the Philippines. The Okinawa flying-fox is extinct; so are the ones from Palau and Reunion. The Solomon Islands lost their endemic tube-nosed fruit bat, while Puerto Rico lost its flower bat. Cuba has lost its red macaw. No one is sure whether turquoise-throated pufflegs exist in Colombia or Ecuador any more. When was the last time any birder you know spotted an Oahu au? A kloea? A Koha grosbeak? A black mamo? Ula-ai-hawane? To add insult to injury, only two reptiles have ever been studied as legitimate pollinators and one of them is already red-listed: Duvau-cel's gecko on a small island off New Zealand.

While rare carnivores and scarce nectar-feeders may differ in their intrinsic perceptibility to humans, they are similar in another way. Both groups of vertebrates demonstrate the connectivity between species essential to the healthy functioning and cohesive structuring of biotic communities. If pollinator guilds are defaunated, animal-pollinated plants that formerly dominated a community are likely to decline. Weedy wind-pollinated plants are likely to find open niches. If carnivore guilds are defaunated, grazing or browsing populations may explode, eliminating herbaceous understories or crippling the recruitment of woody canopy plants. In either case, a shift in vegetation structure results from declines in animal populations which most of us seldom see. In both cases, the natural functioning of a biotic community is disrupted by the demise of ecological relationships between diffusely coevolved associates.

Just as most carnivores rely upon a relatively modest set of prey items, most pollinators depend upon a narrow range of flowering plants that feature certain fragrances, forms, presentations, and nutritional rewards. Coyotes and honeybees may be extreme generalists, but the majority of carnivores and nectar-feeders have limits to what they can opportunistically feed upon; their food choices are not random. in fact, pollinators may generally be more restricted in food choices -- and thus potentially more vulnerable than carnivores.

As the dawn light begins to seep into the canyon shadows, I realize that I have not been selected as a puma prey item at this time. Broadbilled and Costa's hummingbirds arrive to visit the pale blossoms of the Kearney's blue star. So do bee flies and skippers. Not every visitor is an effective pollinator; not every live hunk of meat to visit this canyon gets to sacrifice itself as cougar food.

Gary Paul Nabhan is director of science at the Arizona-Sonora Desert Museum. If we need models of a scientist/organizer/educator of bioregions, Gary is the indicator species. Originator of Native Seed Search (to conserve native American and local cultivars), now involved with setting up Biosphere Reserves along the US/Sonoran border, Gary is prolific, with eight books and dozens of technical reprints. A longer version of this essay appeared in the Fall, 1996 Wild Earth (POB 45, Richmond, VT 05477) and will be included in Gary's Creatures of Habitat, forthcoming from Counterpoint Press.

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