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Society for Conservation Biology: 2002 Annual Meeting

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Society for Conservation Biology: 2002 Annual Meeting


Society for Conservation Biology 16th Annual Meeting July 14-July 19 2002
co-hosted by DICE and the British Ecological Society


Abstracts for Recovery of Endangered Species
Session Two

Wednesday 17th July, 13.30 - 15.00, Grimond Lecture Theatre 1

Chair: Jose Iriondo




(BLOCK CAPITALS indicate the presenting author)


13.30 - 13.45
MALDA-BARRERA, GUADALUPE, Bertha Zúñiga-Tovar and Humberto Suzán-Azpiri. Escuela de Biología, Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, C. U. Cerro de las Campanas, Querétaro, Qro. 76010, México, <gmalda@sunserver.uaq.mx>.

SEEDLING SURVIVAL OF A THREATENED CACTI (LOPHOPHORA DIFFUSSA) UNDER NATURAL AND NURSERY CONDITIONS

Microclimate changes, as a result of habitat destruction in semi-arid regions, are important factors affecting threatened species, particularly small, globular cacti such as the endemic, Mexican species Lophophora diffussa. This contribution analyses some features that determine germination, growth and establishment of plantlets. Nurse plant relationship is essential for the first stages of this cactus, and we recognised the species Larrea tridentata as the major nurse plant associated to this cactus. Micro-environmental conditions offered by this plant are a favourable decrease in extreme temperature and radiation levels, as well as lower humidity fluctuations all year long. L. diffussa seems to produce seeds with low germination capacities, which have an effect on the very low seedling recruitment. Finally, our results suggest that seedlings need to reach a specific size in order to guarantee plantlet survival for the next growth period.

13.45 - 14.00
IRIONDO, JOSE M., María J. Albert, Luis G. Benavides and Adrián Escudero. Departemento de Biología Vegetal, EUITA, Universidad Politécnica de Madrid, E-28040 Madrid, Spain, <iriondo@ccupm.upm.es> (JMI, MJA), Area de Biodiversidad y Conservación, ESCET, Universidad Rey Juan Carlos, E-28933 Móstoles, Spain (LGB, AE).

RESOURCE LIMITATION AFFECTS REPRODUCTIVE SUCCESS IN ENDANGERED ERODIUM PAULARENSE

Erodium paularense plants produce a large amount of flowers but fruit set and seed set values are extremely low. One of the possible causes of this reproductive failure may be resource limitation. To test this hypothesis two field experiments were performed. In the first experiment, treatments including addition of water and/or mineral nutrients (NPK: 15-15-15) were assayed, whereas, in the second experiment, the effect of resource competition by other plants of the community was tested. Watered plants had a longer flowering duration and a greater fruit set than control plants. Mineral nutrient addition did not affect phenological variables nor flower production and, thus, did not influence pollinator activity. However, the addition of mineral nutrients significantly increased fruit set and fruit and seed production. Therefore, part of the low fruit and seed production in natural conditions must be attributed to limiting mineral nutrient resources. The number of flowers and fruits per inflorescence and the number of seeds per fruit were significantly affected by the plant of origin. The elimination of competitors in the second experiment did not affect phenological nor absolute reproductive values. However, fruit set was greater in plants without competition whereas seed set was lower.



14.00 - 14.15
MCCUE, KIMBERLIE A., Missouri Botanical Garden, PO Box 299, St. Louis, MO. USA (kimberlie.mccue@mobot.org)

PROPAGATION OF ENDANGERED ASTRAGALUS BIBULLATUS FOR ESTABLISHMENT OF NEW POPULATIONS IN SITU

The genetic source material for in situ restoration of endangered species must be chosen carefully in order to optimize the likelihood of population persistence. Recently, it has been suggested that seeds collected for use in restoration efforts should be segregated not only by source population, but also by maternal plant to ensure equal familial contribution to the founder population. I examined the importance of maternal line and population sources for restoration of A. bibullatus, a federally endangered endemic that is known only from three populations in Rutherford County, Tennessee, USA. Seeds of A. bibullatus were collected from all three existing populations and sown in the greenhouse using a randomized block design; twelve maternal lines by three populations by three blocks. There were significant differences in germination rates among maternal lines (0.2 percent to 0.8 percent). However, survivorship rates among maternal lines fell within a narrow range (0.6 to 0.8 percent). At the population level seeds from one population had germination rates half that of the other two populations; however, this same population’s seedlings had the highest survivorship rates. Plant restoration efforts should consider the genetic diversity implications of both the population and the maternal line.



14.15 - 14.30
WEEKLEY, CARL W. Archbold Biological Station, P.O. Box 2057, Lake Placid, FL, 33862, USA, <cweekley@archbold-station.org>.

AN INTEGRATED PLAN FOR THE EXPERIMENTAL INTRODUCTION OF ZIZIPHUS CELATA, AN ENDANGERED FLORIDA SHRUB.

Florida ziziphus (Ziziphus celata [Rhamnaceae]) is a woody shrub narrowly endemic to the Lake Wales Ridge of central Florida, USA. Only one of six known populations occurs on a protected wildland site. To develop a recovery program for this imperilled species, we investigated its demography, reproductive biology and genetics. The entire adult population comprises 11 multi-locus genotypes, as determined by allozyme electrophoresis and by RAPDs. In addition to being self-incompatible, many genotypes are also cross-incompatible because they share the same compatibility alleles; to date only three compatible mating types have been identified. Furthermore, seed production is low due to parthenocarpy (seedless fruits) and high levels of seed abortion. Because of self-incompatibility and low genetic diversity, seedling recruitment is unknown from in situ populations. Thus, recovery of Florida ziziphus requires the establishment of sexually-reproducing populations on protected sites. To achieve this goal, we are conducting annual cross-compatibility and germination trials to identify additional compatible mating types. We are implementing an experimental introduction by planting seeds and genotyped seedlings on a protected wildland site. We will compare translocation techniques (planting seedlings vs. sowing seeds) and microhabitat characteristics (e.g., light levels and litter) in order to determine the restoration requirements of Florida ziziphus.



14.30 - 14.45
PINTO-TORRES, ELENA, Suzanne Koptur. Department of Biological Sciences, Florida International University, Miami, Florida 33199, USA, <epinto01@fiu.edu> (EP).

THE POLLINATION AND CONSERVATION OF AN ENDANGERED COASTAL DUNE PLANT

Jacquemontia reclinata (Convolvulaceae), and endangered coastal perennial vine endemic to the barrier islands of southeastern Florida, has become rare due to habitat loss and fragmentation. Wild plants were monitored for pollinator activity at three sites. A diverse group of visitor species was observed, including small to medium bees, flies, beeflies, wasps, and butterflies.



14.45 - 15.00
ADEBOOYE, O.C. Department of Plant Science, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife, Nigeria, <oadeboo@oauife.edu.ng>.

COLLECTION AND EVALUATION OF THE INDIGENOUS FRUITS OF SOUTHWEST NIGERIA.

A mission to collect the endangered indigenous fruits of Southwest Nigeria was conducted in the early and late seasons of 2000 and 2001. The indigenous fruits collected were Carapa procera D. C. (Meliaceae), Synsephalum dulcificum (Schum.& Thonn) Danill (Sapotaceae), Irvingia gabonensis (Aubry-Lecomte. ex. O’Rorke) Baill (Irvingiaceae), Tetracarpidium conophorum (Mull.Arg) Hutch & Dalz (Euphorbiaceae), Spondias mombin L. (Anacardiaceae), Dacryodes edulis (G. Don) H. J. Lam (Burseraceae), Chrysophllum albidium and Parkia biglobosa (Jacq.) R. Br. ex. G. Don f (Mimosaceae). Analysis of chemical and physical characteristics of the fruits showed that S. dulcificum, C. procera and S. mombin are good sources of proteinaceous phytosucrose, I. gabonensis (two varieties) are potential sources of fat and oil, while D. edulis and C. albidium are good sources of protein and vitamins for human health. All the collected species are endangered and decimated due to neglect by research and development. Results showed that the harvesting methods used for these plants often destroy the remaining few stands in Southwest Nigeria. At least two morphological variants of each species were collected. Each of the species collected have indigenous medicinal uses among the Yoruba people of Southwest Nigeria.