A novel approach to growing mangroves on the coastal mud flats of Eritrea with the potential for relieving regional poverty and hunger: comment

Abstract

The paper by Sato et al. published in Wetlands (Vol. 25, No. 3, pp. 776–779) describes an obviously wellmeaning attempt to afforest self-described ‘‘. . . treeless mud flats of Eritrea. . . where trees had not grown before. . . ’’ (p. 776–777) with seeds and seedlings of Avicennia marina (Forsk.) Vierh. The intent is to provide ‘‘. . . recently weaned sheep. . . ’’ with ‘‘a diet of dried mangrove seeds and foliage,’’ plus supplemental diet items in an attempt to alleviate local poverty and food availability issues. To this locally focused end, we applaud these efforts. However, beyond the local poverty issues, the paper suggests that the methodology described has ‘‘. . . the potential to create a cost-effective sea-water agriculture and eliminate hunger and poverty in many regions of the world ‘‘(p. 779). In addition, it suggests that ‘‘(E)ven in tropical countries . . . we can increase mangrove forests by widening the growth area by fertilization’’ (page 779). We do not believe that the data presented support this contention, and they ignore the major factors that control natural or human-assisted mangrove afforestation efforts on subtidal mud flats. In addition, several papers of importance to the issue are not referenced. In a recent review on the existing knowledge about mangrove restoration (Lewis 2005), a large number of failed attempts to establish mangroves were documented. Specifically, this review stated the following.