A Survey of Bern Convention Plant Taxa in European Botanic Gardens: Initial Findings and Implications
Volume 2 Number 10 - June 1998
Mike Maunder and Sarah Higgens
On behalf of the BGCI/IABG European Botanic Gardens Consortium a survey was undertaken by the Conservation Projects Development Unit to assess current holdings of European threatened plant species and ongoing plant conservation projects. This study was funded by the Living Collections Department of the Royal Botanic Gardens, Kew, and complements a survey undertaken by the Conventions and Policy Section of RBG Kew "The Trade Status of Plants on the EU Habitats Directive" (Crook, 1994). The survey used the list of species cited in Appendix I of the Bern Convention on the Conservation of European Wildlife and Natural Habitats. The spelling and authorities adhere to the version of the Appendix revised on 13th March, 1996, and available on the internet at:
A total of 624 botanic gardens/institutions in 40 countries were contacted, 105 botanic gardens in 29 countries responded. This report presents the initial findings. It is proposed that the survey will be expanded in the future to encompass species listed in the Habitats Directive and recent Eastern European additions to the Bern Convention.
The results of this survey illustrate general trends in the representation of Bern Convention taxa in European botanic gardens. The data pertaining to accessions must be treated with caution as the interpretation of this term is not uniform. The names were accepted as submitted and identities not checked.
Representation of Bern Convention Taxa in Botanic Gardens
A total of 573 plant taxa are listed in the Bern Convention, with 308 taxa listed from the replying institutions as in cultivation (53.8% representation). A total of 4,417 accessions were recorded, with 39% recorded as of wild origin. Seed stocks were held for 210 different species (68.2% of species recorded). It is apparent that certain families have higher levels of representation than others.
How are they Distributed Throughout the European Collections?
Bern Convention taxa are not uniformly distributed throughout collections. It is evident that a large number of commonly cultivated species are found in a majority of collections. Ten commonly cultivated taxa (3.2% of taxa) account for 29% of all accessions. In contrast, a number of taxa are very restricted in cultivation, 195 taxa are cultivated in three or less collections (63% of cultivated taxa).
Many Taxa are Cultivated in a Small Number of Collections.
89 taxa are cultivated in one botanic garden only;
63 taxa are cultivated in two botanic gardens only;
43 taxa are cultivated in three botanic gardens only.
Certain botanic gardens have particularly rich collections.
It is evident that botanic gardens vary in the size and quality of collections. Within Europe the largest collections of Bern Convention species also hold the largest numbers of unique holdings.
Quality of These Accessions
The majority of Bern Convention accessions are not of wild origin and are presumably either old un-documented specimens or material derived from other botanic gardens. It is suspected that a large number are regularly exchanged through seed lists with little accompanying data (accessional or genetic). Of the accessions reviewed only 39% are recorded as wild origin. A number of species are represented in cultivation by a relatively large number of wild accessions.
European Plant Conservation Projects
The majority of accessions are not linked to any formal conservation programme. A total of 345 conservation projects were recorded with 44 projects at 23 institutions specifically focused on 27 Bern Convention taxa.
European botanic gardens are cultivating extensive collections of threatened European plant taxa, 105 European botanic gardens are growing 308 of the 573 plant species listed by the Bern Convention. European botanic gardens have maintained samples of at least six European plant taxa listed as "Extinct in the Wild" sensu IUCN.
European botanic gardens have a proven horticultural ability to maintain specimens of a diverse taxonomic and ecological character. Many botanic gardens are undertaking recovery and reintroduction projects for threatened species; a total of 44 projects for Bern Convention taxa are recorded from 23 institutions. For some taxa the numbers of specimens in botanic garden collections exceed existing wild populations, e.g. Echium pininana, Silene hifacensis, Geranium maderense etc. Old and historical collections may contain representatives of provenances/populations now lost, e.g. Astragalus physocalyx.
However, the survey and associated projects reveals a number of serious problems in the management of threatened plant taxa within European botanic gardens. There is considerable confusion with terminology and no accepted European standards of practice for the management of threatened plant taxa in cultivation. Currently stock is being dispersed between collections with no method to track pedigrees.
No mechanism currently exists to co-ordinate the management of cultivated stocks or to locate and utilise specific resources and facilities. The majority of taxa are represented by single accessions scattered through collections with no co-ordinated management between gardens and management agencies. The majority of accessions are not of known wild origin and carry little associated documentation. There are also very low levels of intraspecific sampling, as indicated by the low numbers of accessions per taxa.
The majority of accessions held are not utilised for ongoing conservation projects. Large collections of Bern Convention taxa are held out of the range countries e.g. within UK, German and French collections.
Most collection holders have accumulated horticulturally robust and ornamental taxa. There in increasing evidence (Maunder and Culham unpublished data) that botanic garden stocks of short lived species are subject to high levels of hybridisation. This is particularly problematic for species with short generation times and weak interspecific barriers to hybridisation e.g. Echium section Simplicia from the Canary Islands.
There is an urgent need to increase capacity in data management and exchange between European botanic gardens.
How can the European Botanic Gardens Effectively Contribute to Plant Conservation?
There is an opportunity to move botanic gardens from being often regarded as peripheral agencies for plant conservation towards playing a scientifically based and realistic role in supporting the conservation of wild populations and habitats. To effectively contribute to plant conservation it is necessary that botanic gardens further develop close working relationships with the biodiversity and protected area agencies. Ideally the wild and cultivated populations of "Critically Endangered" taxa should be managed as a whole. This will necessitate the development of national and European working groups.
Existing botanic garden collections should be used for conservation purposes only with extreme caution. The majority of accessions are derived from cultivated stock and will represent a small sub-set of the wild genetic diversity. Accordingly, the emphasis for activity should shift from the collection towards the botanic garden's capacity in terms of facilities, location and skilled horticultural and botanical personnel. The long term holding of cultivated conservation collections of threatened taxa in botanic gardens should be discouraged in favour of developing botanic gardens as short-term processing facilities with seedbanks holding long-term collections.
It will be important to establish European standards for genetic and demographic management of conservation collections, utilising existing protocols/vocabulary established by such organizations as BGCI, IUCN/SSC, CPC, IPGRI etc. Mechanisms should be developed to identify those plant species requiring ex situ conservation and of what sort. Only a proportion of Europe's threatened plant species will require ex situ support, these should be identified and priorities for action established. In-country programmes should be promoted that are based on national and European priorities, e.g. listings from Biodiversity Action Plans and the European Plant Specialist Group of the SSC. Particular emphasis should be given to high diversity areas with poorly developed conservation infrastructure.
It is important that close collaboration be established by botanic gardens with biodiversity and protected area agencies and explore the options for managing populations on site in the habitat e.g. micro-reserves. Electronic information exchange capacity needs to be developed within European botanic gardens; and encourage the exchange of scientific and horticultural expertise through publications and working group reports. Practical training courses in plant conservation techniques, promoting integrated management of populations should also be co-ordinated and developed by national networks. It will also be valuable to link this work with botanic garden education programmes to use urban botanic gardens as a means of promoting local and European plant conservation issues.