Conservation Status and Protection Measures for the Spanish Endemic Plant Sideritis Borgiae Andrés
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International Journal of Geobotanical Research, Vol. nº 2. 2012. pp. 1-12 Conservation status and protection measures for the Spanish endemic plant Sideritis borgiae Andrés Raquel ALONSO-REDONDO, Estrella ALFARO, Elena DE PAZ & Marta E. GARCÍA-GONZÁLEZ Botany Section, Department of Biodiversity and Environmental Management, Faculty of Biological and Environmental Sciences, University of Leon, Vegazana Campus, E-24071 Leon. Abstract Sideritis borgiae is an endemic plant restricted to a small area in the Castilla y León Region of Spain, included in the regional pro- tection catalogue. This paper provides a complete study of the currently known populations, with the aim of assigning the conserva- tion status of the taxon in accordance with IUCN criteria using RAMAS Red List 3.0 software, as well as detecting risk factors and providing appropriate management measures to guarantee survival of the taxon. In addition, the taxonomic status is discussed and we provide chorological, biological and ecological data of interest. Keywords: conservation, IUCN, RAMAS Red List, Sideritis borgiae, Spain.. Introduction Until now, no studies had previously been conducted to determine its area of occupancy or extent of occurren- Sideritis borgiae Andrés is a taxon endemic to Spain ce for cataloguing according to IUCN criteria, and this which is distributed throughout the northwest Iberian article therefore presents the first results obtained for quadrant and has been the subject of various conserva- IUCN cataloguing, using the RAMAS Red List 3.0 pro- tion and taxonomy studies. It was included in the Spa- gramme. To this end, an extensive literature search was nish Red List of Vascular Flora published in 2000, under conducted, considering taxonomy, chorology, biology, the category DD (data deficient) (Domínguez, 2000), due ecology and conservation, and new data was also provi- both to lack of knowledge about its distribution and the ded by the authors of this study. The study also included problems it presents at taxonomic level. However, it was the compilation of all known factors posing real and removed when the Spanish Red List of Vascular Flora potential threats to the species. under Threat was published in 2008 (Moreno, 2008), as Sideritis borgiae was first described by Andrés (López it was considered to form part of the broader taxon, S. Pacheco et al., 1979), on the basis of material found in lurida J.Gay. At present, within the Autonomous Region the province of León. In 1994, Obón & Rivera subordi- it appears in Decree 63/2007 of the 14th of June, esta- nated the plants from the Sierra de Gredos (Ávila) under blishing the creation of the Catalogue of Protected Flora S. borgiae with sub-species rank: S. borgiae subsp. rele- of Castilla y León and the protection mechanism known gata (Font Quer) Obón & D.Rivera. as the Micro-Reserve for Flora, in the category “Prefe- In 2000, Luceño et al. included all previous materials rential treatment”, a category which is assigned to scarce in the combination S. lurida subsp. borgiae, considered species in Castilla y León which present reduced popu- to encompass the populations from Ávila, León and lations that could be affected by various disturbances, or Orense, whilst the typical sub-species included the po- that are associated with retreating or threatened habitats. pulations from Asturias. In the case of S. borgiae, this category is justified by In 2002, Rivas Martínez et al. subordinated the po- both the plant’s rarity and the lack of knowledge regar- pulations from Ávila, once again with sub-species rank, ding its distribution. It also appears in the Cantabrian but this time under S. lurida. Flora of Interest in Castilla y León (Llamas et al., 2007), Later, in 2010, Morales reported that all the pre- where it has been catalogued as a very rare plant (RR). viously mentioned materials corresponded to a single At a local level, it appears in the Lists of Flora under taxon, S. lurida, with no infra-species variation. Threat maintained by the provinces of Leon and Palencia It is our opinion that two species exist, S. lurida and (Llamas et al., 2003a, b). S. borgiae, distinguished by the shape and size of the bracts and the number and length of the bract teeth. Corresponding author: Raquel Alonso-Redondo. Botany Section, Department of Biodiversity and Environmental Management, Faculty of Biological and Environmental Sciences, University of Leon, Vegazana Campus, E-24071 Leon. e-mail: [email protected] ISSN: 2253-6302 (print)/ISSN: 2253-6515 (on line) ©Editaefa DOI: 10.5616/ijgr 120001 2 R. Alonso, E. Alfaro, E. de Paz & M.E. García Materials and Methods occurrence, and criterion B2 to calculate area of occu- In order to evaluate the state of the taxon in accor- pancy. It also considers the possible existence of conti- dance with IUCN criteria (IUCN, 2001), an exhaustive nuous decline and/or extreme fluctuations in both cases. literature review was first completed. In addition to jour- The programme provides options for calculating both nals, monographs and floras in use, the Information extent of occurrence and area of occupancy as fuzzy System on Spanish Plants (Anthos, http://www.anthos.es), numbers using spatial uncertainty and observation relia- the National Node for Biodiversity Information (GBIF-Es, bility measures (Akçakaya & Ferson, 2007). The Spatial http://www.gbif.es) and the Database of Vascular Flora Analysis module calculates the extent of occurrence of Castilla y León (Various Authors, 2007-2008) were based on Delauney triangulation but also allows for the consulted for this review, together with the material exclusion of some of the triangles included in the poly- deposited in the MA, SALA and LEB (Annexe 1) herba- gon generated. An alpha-hull was used to control the ria. exclusion of surface areas, so that the programme exclu- Based on an analysis of the literature and study of the materials, we have selected the citations we consider ded any triangle whose perimeter was greater than the correct and which are, in our opinion, the only ones average perimeter of all triangles multiplied by a speci- which correspond to the taxon S. borgiae. Such prior fied value (α), in this case, α=2. analysis was essential, since this is a controversial taxon The Spatial Analysis module also permits the incor- as regards its taxonomic category and nomenclature. poration of uncertainty and reliability data regarding Furthermore, it was of particular importance to exercise locality. Thus, it was possible to take into account the rigour in these preliminary taxonomic and chorological fact that not all citations provided the same level of geo- studies due to the considerable influence they would graphic precision, as mentioned previously (uncertainty), have on the results, which in turn would determine the and were not all equally reliable, since although the category of threat assigned to the taxon. majority of the citations considered had supporting spe- The selected citations were used to generate a layer cimen sheets, all of which were revised (maximum relia- of points representing the real distribution of the taxon bility), there was one citation which we were unable to using Arc GIS 9.2. software. For the final map, the back- verify as the corresponding herbarium specimen sheet ground was constructed using a geo-referenced ortho- appeared to have been lost and could not be located photo obtained from the Landsat satellite (minimum reliability). This citation, considered unrelia- ble, corresponded to Quintana del Puente, a locality in (www.ign.es/iberpix/visoriberpix/visorign.html). the province of Palencia (LEB 29499). It should be noted that the precision of the citations Both uncertainty and reliability of the citations were was not always the same; in some cases, a point marked with GPS in the field was available, but in the case of incorporated into the programme as a database field older citations, sometimes only a 10 x 10 or 1 x 1 UTM containing the points considered and the categories grid reference was available, or a toponymic reference to assigned in each case according to the following criteria: the closest municipality, site or urban centre. Conse- In the case of uncertainty, 3 categories were assigned quently, in order to georeference the citations according with their corresponding radius of uncertainty (in me- to the level of information in each case, 10 x 10 UTM tres): grid cell centroids were used, together with 1 x 1 UTM ● 0: for citations providing GPS references, with a ra- grid cell centroids, municipality centroids or the exact dius of uncertainty of 0 m GPS location. ● 1: for citations georeferenced as 1x1 UTM grid cell In assigning conservation status, 2001 IUCN criteria centroids, with a radius of uncertainty of 1000 m were followed and to ensure the evaluation was as ob- ● 2: 2 for citations georeferenced as 10x10 UTM grid jective as possible, the RAMAS Red List programme cell centroids or municipal centroids, with a radius of (Akçakaya & Ferson, 2007) was used. This programme uncertainty of 10000 m is a very useful tool, enabling species under threat to be In the case of reliability, 2 categories were assigned: catalogued quickly and objectively. It has already been used with success to catalogue other endemic Iberian ● 0: for minimum reliability (citations without herba- flora with a restricted distribution (Navarro et al., 2003; rium specimen sheets) García-González et al., in press). As it is an endemic ● 1: for maximum reliability (citations with herbarium plant exclusive to these territories, the taxon evaluation is specimen sheets, revised and verified) presented as a global assessment. The terms “popula- By incorporating uncertainty into the calculation of tion”, “sub-population” and “locality” have been used in extent of occurrence and area of occupancy, it was po- accordance with Bañares et al.