Status of Hagenia forest in the Parc National des Volcans, Rwanda: A review of historical records

Abstract

Hagenia-shaped habitat is an important element in conservation of world's only population of mountain gorillas surviving in the wild. In fact, in the Parc National des Volcans (henceforth PNV), gorillas spend most of their life time in the nutritious herbaceous habitats near or within the Hagenia-Hypericum zone. Unfortunately, populations of Hagenia abyssinica in this park have been reported to be ageing. Using information drawn from the statistical analysis of records in herbaria and the cross−examination of the literature, the status of Hagenia forest in PNV is discussed. The results show that H. abyssinica in PNV has an unusual pattern of population structure and distribution, seemingly since many decades. No record of H. abyssinica was collected from PNV, but patterns of collections of H. abyssinica are globally similar to those of a set of five control tree species, such that this absence of records from this park cannot be considered as due to collector or collection site-bound bias. The paper ends by giving insight on possible implications for conservation of the park's wildlife, chiefly the gorillas.

The complete chloroplast genome sequence of an endemic monotypic genusHagenia(Rosaceae): structural comparative analysis, gene content and microsatellite detection

“…Over the past few decades, there has been a vast reduction of natural populations of this species resulting from overharvesting, selective logging and habitat destruction. Consequently, H. abyssinica is now listed in the Red List of endangered species in Ethiopia and other regions where assessment has been done in eastern Africa (Negash, 1995; Vivero, Kelbessa & Demissew, 2005; Seburanga, Nsanzurwimo & Folega, 2014). …”

Caractérisations Structurale, Floristique Et Biomasse Ligneuse Du Peuplement À Hagenia abyssinica Du Parc National De Kahuzi-Biega (Rift Albertin, RDC)

“…Cependant, pour les sites de Kasirusiru et Mugaba où la dynamique est progressive, on observe une bonne régénération avec plusieurs pousses de H. abyssinica et un très faible taux de mortalité (133/344). Dans la région du Rift albertin, il se pose déjà la question sur le statut de cette formation endémique de montagne (Feyissa et al, 2007;Seburanga et al, 2014). D'aucun pense qu'un faible changement de la température dans cette zone (Akonkwa et al, 2015) pourrait influencer la diversité biologique dans sa composition et sa structure.…”

“…Parmi ces communautés, on retrouve les groupements de Hagenia abyssinica. En général, ce groupement se situe entre 1800 et 3400 m d'altitude dans la région afro-montagnarde (White, 1993;Seburanga et al, 2014) et entre 2000 et 2600 m dans le contexte du PNKB (Pierlot, 1966).…”

Observations on regeneration of the keystone plant species Hagenia abyssinica in Volcanoes National Park, Rwanda

“…Certain keystone plant species play an irreplaceable role in the generation and maintenance of faunal and floral diversity (Mills, Soulé, & Doak, ; Peres, ). Hagenia abyssinica (hereafter Hagenia) is a montane flowering plant endemic to Central and East Africa (Feyissa, Nybom, Bartish, & Welander, ) and provides habitat and food to a wide variety of organisms, including the tree hyrax ( Dendrohyrax arboreus ) and the critically endangered mountain gorilla ( Gorilla beringei beringei ) (Grueter et al, ; Milner & Harris, ; Seburanga, Nsanzurwimo, & Folega, ). In Volcanoes National Park (VNP), Rwanda, Hagenia is one of the dominant tree species of a forest habitat in which the mountain gorillas spend a large amount of their time, with an associated understory comprised of food plants for mountain gorillas (Kayijamahe, ; Watts, ).…”