I have been conducting research in the sand-dune ecosystems on the north shore of Mono Lake since 1978, on several inter-related projects.  This work began in 1978 with my intitial studies of the bee-fly (family Bombyliidae) communities, which are particularly species-rich on sandy substrates, in the California deserts. The bee-fly studies then focussed on the demography and behavioral ecology of  two congeners, Lordotus pulchrissimus and L. miscellus, both of which have life histories and mating systems centered around the annual flowering of rabbitbrush, Chrysothamnus nauseosus.  Understanding the mating systems and the spatial structure of these two species of Lordotus required increasing information on the "habitat" of these bee flies, leadiing to extensive studies of the sand-dune ecosystem, which is the current focus of my research.  In 1983, we initiated demographic studies of rabbitbrush, later adding greasewood (Sarcobatus vermiculatus) and in 1988 began vegetation studies of the dune communities.  By the 1990's I brought in collaborators (Dr. Deborah Elliott-Fisk, physical geographer and plant ecologist; Dr. James H. Richards and Dr. Lisa A. Donovan , plant physiological ecologists) to undergo a more comprehensive study of the sand-dune ecosystem and its development as revealed on shorelines of differing ages (as Mono Lake regressed during natural long-term climate change and diversion of water for urban uses).  Most recently this work as received major funding from National Science Foundation and the U.S.D.A. Competitive Grants program.

 

Community ecology of bee flies (family Bombyliidae)

Demography and behavioral ecology of Lordotus pulchrissimus and L. miscellus

Development of sand-dune ecosystems through the recent Holocene

Demography of desert phreatophytic shrubs:  Desert dogma tested

Mono Lake is a terminal Great Basin lake, bounded on the west by the Sierra Nevada and on the other sides by lower ranges in the Basin and Range Province. This picture (USGS) shows the historic lake at 6400' surface elevation. Holocene shorelines can easily be seen in the basin in the lower part of the photo, as the lake regressed from the pluvial high stand of former Lake Russell ca. 13,000 yr bp as a result of long-term climate change. Water enters Mono Lake by streams originating in the ranges forming the basin; most of the lake's water comes from 4 streams originating in the high Sierra (Walker, Parker, Lee Vining and Miller) and leaves only by evaporation. Because evaporation has exceeded input over the past 10,000 years, Mono Lake is highly alkaline and saline. These conditions challenge plants that attempt to establish on shoreline strands of the regressing
lake.

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