Carnivorous Plants and Their Prey

through times when insect pollinators are not present (44). Whether because of a general
shortage of possible insect pollinators, inadequate flower visitations, or the loss of potential
vectors to traps, self-fertilization appears to be an important reproductive strategy among some
carnivorous species (45). Even species that appear to be insect-pollinated such as Darlingtonia
californica may depend on self-fertilization until rare pollinators visit (66). Some species that
self-pollinate may still be dependent on insect vectors for movement of pollen from anther to
stigma within a given flower and thereby show facilitated self-compatibility. Anderson et al. (72)
found a reduction in self-pollination when Pameridea bugs were not present on Roridula flowers.
When Pameridea were present, R. dentata showed a 68% fruit set while R. gorgonias had 25%
fruit set. Pameridea, however, seldom move from one flower to another and thereby severely
preclude cross-pollination (17, 72). In Drosera anglica, seed set and seeds per fruit from self-
pollination were comparable to that afforded by insect vectors. Findings such as these apparently
indicate autogamy as the primary reproductive strategy among certain carnivorous species (44).
Other species such as Darlingtonia californica, although self-compatible, have flowers that
appear to be constructed in such a way as to promote cross-pollination while dissuading self-
pollination (11, 29). Self-compatibility may provide viable offspring but it seems to be
counterproductive to the long-term survival of a species (45, 72). Cross-pollination may be a rare
but necessary event with some carnivorous species, especially those that show facilitated self-
compatibility (45).
Vegetative propagation is an important reproductive strategy for carnivorous plants and
may provide another means for carnivorous plants to lesson pollinator-prey conflicts (64). Most
carnivorous plants tend to be long-lived perennials, often relying on asexual reproduction during
some part of their lives (13, 64). Darlingtonia californica, for instance, depends heavily on
stoloniferous growth to produce new plants (11, 29). Asexual production of tissue is a less
expensive reproductive effort, both with respect to energy costs (manufacturing of pollen, nectar,
flowers, embryos, etc.) as well as time demands to produce a new, mature plant (29). For such
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