In situ and Ex situ Conservation of Commercial Tropical Trees - ITTO

202DiscussionThe ex situ conservation stands of tropical pines were generally well establishedand managed in the initial stages. Sufficient financial resources were allocatedto early stand management. However, it was much more difficult to ensurelong term management of the stands. Thinning and fire protection were oftenneglected, which substantially reduced the conservation value and success ofthe project. As a result, the stands have been characterised as the ‘forgottenstands’ - they were established but largely set aside and not managed or used.At the time of establishment there was national interest in using thespecies and provenances in question for local plantation purposes. Hence, thepurpose of the stands was both conservation and seed supply. The demand forseed for these species was much lower than anticipated seriously hamperingthe incentive to actively manage the stands. Most methods of ex situ preservationof live plant material require periodic regeneration and sexual reproduction ofthe stock. At present, regeneration of the ex situ stands included in this studyseems unlikely. The costs involved and the poor prospects for recovering partof the expenses by seed sales probably hamper the interest of institutions incharge to regenerate the stands at the end of their rotation. As a basis fordeciding how, -and, which of the stands to manage in the future, it isrecommended that institutions in charge carefully evaluate the potential useand seed requirements of the species/provenances, define national conservationpriorities and take action in accordance with these priorities.Although a particular stand may have limited conservation or economicvalue from a national perspective it may still be valuable from an internationalconservation perspective. Hence, assessment of the international conservationvalue, identifying how stands may fit into an overall conservation network andthereby contribute to the conservation of genetic resources of the species, isimportant. Information on the present conservation status of the naturalpopulations in situ complemented with information on other ex situ initiativeshas been compiled by CAMCORE (2000). Based on this information it appearsthe stands with the highest international value are the P. caribaea, lowlandprovenances of Guanaja and Karawala together with P. tecunumaniiprovenances of San Rafael and Yucul. Stands of high priority internationallyare indicated in Table 1.For stands recognised for their national or international conservationvalue future management steps should be considered. Thinning measures toattempt to develop seed production from the better phenotypes is recommended.At the end of their rotation it would be desirable to collect seed and replant theblock to the same number of individuals or larger. It is likely, however, that theeffective population size will be substantially reduced, perhaps in the order of