Conservation of native trees and the indigenous bees in Costa Rica: nest tree

selectivity and melliferous plants

Luis Sánchez Ch. and Ingrid Aguilar M.

Introduction

√ Stingless bees inhabitants of tropical regions

Introduction

STINGLESS BEES DIVERSITY(APIDAE: MELIPONINI)

Around 400 species in the world

√ In Costa Rica: 60 species, 15%

Introduction

√ 12 genera Trigona, one genus Melipona

STINGLESS BEES DIVERSITY(APIDAE: MELIPONINI)

Introduction

√ Live permanent colonies

Introduction

√ Generalist in the use of food sources

The species specific characteristics (bee size,

colony size, communication, etc.) play a role in the

distention of the trophic niche for every species.

Introduction

√ Important pollinators of many flowering plants

Melipona beecheii

According Roubik: “ SB the most important insect groups, in pollination of native flora: GREAT DIVERSITY & HIGH ABUNDANCE

Main objective

The aims of this study was to increase our knowledge about the principal plants species that are used as pollen resources by the stingless bee species and nest site selection in a tropical dry area of Costa Rica.

Aspects studied

• January to April 1997, pollen loads were collected bi-weekly from returning foragers of Tetragonisca angustula. While, pollen from flowering plants was taken to create a reference collection of the pollen types.

• Inventory of all trees (trunk diameter at breast height (dbh) ≥ 20 cm (forest plot 1ha; farm plot 5.8h).

• Pozo Azul de Abangares, Guanacaste Province.

Results: Pollen spectrum

• T. angustula collected a total number of 32 pollen types

• Asteraceae, Fabaceae and Sapindaceae were the dominant families in three colonies of T. angustula.

• Simpson’s index was 0.52 (intermediate record of diversity)

• Guazuma ulmifolia, Sapindus saponaria and Trema micrantha dominated in several weeks

Results: Pollen spectrum

Guazuma ulmifolia Lam. Sapindus saponaria L. Trema micrantha (L) Blume

Table 1. Species collected by Tetragonisca angustula

Family Species Form Type /blossom

Acanthaceae Bravaisia intigerrima (Spreng.) Standl. Tree/ medium size ++Anacardiaceae Anacardium excelsum (Bert. & Balb.)

Skeels.Tree/large ++

Asteraceae Calea urticifolia (Mill.) DC. herb ++Asteraceae Vernonia patens HBK. Shrub ++Asteraceae Aster sp herb -Asteraceae Asteraceae type 1 herb (commonly) -Bombacaceae Pseudobombax sp Tree/usually large +Boraginaceae Cordia alliodora (Ruiz & Pavón) Tree/large-medium size ++Burseraceae Bursera simaruba (L.) Sarg. Tree/small -large ++Combretaceae Combretum fructicosum HBK. Vine -Fabaceae Gliricidia sepium (Jacq.) Steud. Walp. Tree/medium size -Fabaceae Fabaceae type 25 Many formsLabiatae Hyptis suavelons L. Point herb +Lauraceae Ocotea veraguensis (Meissn.) Tree/large +Malpighiaceae Banipteriopsis sp Liana -Moraceae Ficus sp Tree/large +Myrtaceae Psidium guajaba L. Shrub or small tree -Palmae Acromia vinifera Oerst. Tree/large +Piperaceae Piper aduncum L. Heb-shrubby -Piperaceae Piper marginatum Jacq. Heb-shrubby -Polygonaceae Triplaris melaenodendrum (L.)

Meissn.Tree medium size/shrub ++

Rutaceae Citrus sp Shrub -Sapindaceae Sapindus saponaria L. Tree small or medium ++Sapindaceae Sapindaceae type 31 Tree usually large ++Sterculiaceae Guazuma ulmifolia Lam. Tree small medium size ++Tiliaceae Corchorus siliquosus L. Shrub -Nota: ++ floración masiva, + floración moderada, - flores solitarias

Blooming syndromes. Plant species used by T. angustula

• ++ Massive Blossom 12

• + Moderable Blossom 7

• - Solitary flowers 6

Andira inermis

Cordia alliodora

Cochlospermum vitifolium

Blooming syndromes. Plant species used by T. angustula

• ++ Massive Blossom syndrome

CONSIDERATIONS

“Despite feed resources are plenty to the bees. They are moving between the massive blossom trees, checking the sudden changes on nectar concentration…..More # of visits to flower of different individuals……MORE CROSS-POLLINATION” (Frankie & Haber, 1983).

Way of nectar

Dioicium

Before 70ts tress> self-compatibles…. Hyper-dispersion

Self-incompatibility are prevalent dioics are frequent

CROSS-POLLINATION services

Tree species Bee species

• Anacardiun excelsum Scaptotrigona pectoralis

• Bravaisia integerrima Scaptotrigona pectoralis

• Clarisia biflora Scaptotrigona pectoralis, Oxytrigona mellicolor, Tetragonisca angustula

• Cordia alliodora Tetragona dorsalis ziegleri,Tetragonisca angustula,Nannotrigona testaceircornis perilampoides

• Diphysa americana Tetragonisca angustula• Ficus sp. Scaptotrigona pectoralis, Melipona beecheii

• Ficus trachelosyce Tetragonisca angustula

• Gliricidia sepium Tetragonisca angustula

• Lonchocarpus lasiotropis Nannotrigona testaceircornis perilampoides

• Myrospermum frutescens Cephalotrigona capitata zexmeniae

• Tabebuia ochracea Cephalotrigona capitata zexmeniae

Table 2. Tree species/ nest site selection reported (Apidae,Meliponini)

Tree species # bee species Country Reported use________________________________________________________Pithecellobium saman* 4 Venezuela N, 1, 2,3Spondias mombin* 1 Venezuela P, N, 1,2Albizia caribensis* 3 Venezuela -Lonchocarpus pictus* 2 Venezuela P, N, 1, 2Anarcadium excelsum ** 1 Costa Rica N, 1, 3Ficus sp**+*** 2 Costa Rica P,2Lonchocarpus lasiotropis ** 1 Costa Rica -Ficus trachelosyce ** 1 Costa Rica P, 2Bravaisia integerrima ** 1 Costa Rica N, P, 2Clarisia biflora ** 3 Costa Rica -Tabebuia ochracea** 1 Costa Rica N, 1, 3Diiphysa americana** 1 Costa Rica 3Cordia alliodora** 3 Costa Rica P, N, 1, 2, 3Myrospermum frutescens** 2 Costa Rica N,1, 3Bursera simaruba** 1 Costa Rica P, 1, 2, 3Gliricidia sepium**+*** 1 Costa Rica P,N, 1, 2, 3--------------------------------------------------------------------------------------------------*: Moreno and Cardozo, 1997 **: Aguilar and Berrocal, 1997 ***: Sánchez, 1999. Data not publ.N: nectar, P: pollen 1: honey bees, 2:Stingless bees, 3: other functions

Conclusions

• Fabaceae, Asteraceae and Sapindaceae are important families in the pollen diet of the bees

• Inga vera, Cordia alliodora and Triplaris melaenodendrum all important nectar sources, honey bees also collect pollen of these plants species in larger quantities

• Pollen, collected from mass flowering plants, during a short period of time

• The spatial distribution of resources influence diversity of pollen collected by Trigona species.

• Deforestation have an effect on population structure (e.g. abundance).

• Nest selection and available food sources may limit colony reproduction in several stingless bee species.

Thank you !