Influences of Long-Term Changes in Land Cover on Mammal Populations: an Example from Mexico

Home , Mara (mammal), Tehuantepec jackrabbit, Volcano rabbit

Influences of long-term changes in land cover on mammal populations: an example from Mexico

C ONSUELO L ORENZO,EUGENIA C. SÁNTIZ J ORGE B OLAÑOS-CITALÁN and D ARÍO N AVARRETE-GUTIÉRREZ

Abstract Changes in vegetative cover and land use in the growth (Mas et al., ; Nájera et al., ), which increases southern part of the Isthmus of Tehuantepec in Oaxaca, demand for space for housing and food production, and Mexico, were identified by analysing satellite images from poor agricultural management, particularly with respect to  and . Fluctuations in population density of mam- livestock raising and prescribed burning of pastures (uncon- mal species during – in response to these changes trolled burning of grasses to promote new growth of grazing were analysed. During – the types of land use that pasture for cattle) for seasonal crops (López-Granados et al., increased in area (per year) were prescribed burning (un- ; Peralta-Rivero et al., ). Both of these matters have controlled burning caused by humans) by . ha, seasonal led to reduction, degradation and fragmentation of habitat agricultural plots by . ha, areas without vegetation by (Bender et al., ; Rioja et al., ; Lorenzo et al., ), . ha, and human settlements by . ha. In the same directly affecting the amount and quality of vegetation, as period, savannahs decreased by . ha, tropical dry forest well as food availability for wild animals. by . ha, secondary forests by . ha, and human- In the southern region of the Isthmus of Tehuantepec, induced grassland by . ha per year. The loss of these habitat consists of scrub and mangrove, with submerged vege- habitats resulted in low population densities of mammals, tation in coastal lagoons (Superior Lagoon and Inferior including the eastern cottontail Sylvilagus floridanus and Lagoon; Ortiz et al., ), as well as extensive areas of savan- the Tehuantepec jackrabbit Lepus flavigularis, which is cate- nah with isolated shrubs and trees (Rzedowski, ;Sántiz gorized as Endangered on the IUCN Red List. We recom- et al., ). Large areas of low tropical deciduous and low de- mend establishing a communal ecological reserve in the ciduous forest (Torres-Colín, ), as well as savannahs and study area to implement appropriate management strategies human-induced grasslands (native or exotic species that for grassland communities and develop a programme of develop in sites in which the original vegetation has been semi-captive breeding to conserve L. flavigularis. eliminated or in abandoned agricultural areas; Aristida, Bouteloua, Cathestecum, Cenchrus, Digitaria, Eragrostis, Keywords Carnivores, conservation, land management, Panicum, Paspalum and Schizachyrium) are found in this land use, Lepus flavigularis, Oaxaca, population density, region (Rzedowski, ;INEGI,;Sántizetal.,). Sylvilagus floridanus Grasslands of the Isthmus of Tehuantepec have been transformed for agriculture and livestock raising, causing degradation and reduction of the original vegetation (Sántiz et al., ). One mammal species of the region Introduction that depends on savannahs and human-induced grasslands is the endemic Tehuantepec jackrabbit Lepus flavigularis n tropical regions changes in land use have been the main (Anderson & Gaunt, ; Lorenzo et al., ), which is ca- Icause of biodiversity loss, with the associated loss of tegorized as Endangered on the IUCN Red List (Cervantes  habitats for wild flora and fauna (Arriaga & Gómez, ; et al., ). This lagomorph shares its habitat with other   González et al., ; INEGI, ). The principal causes of lagomorphs, such as the eastern cottontail Sylvilagus florida- changes in vegetative cover and land use on the Isthmus of nus, as well as their predators: the coyote Canis latrans and Tehuantepec in Oaxaca, Mexico, are human population the grey fox Urocyon cinereoargenteus (Lorenzo et al., ; López et al., ). Interactions among taxa influence abundance and dens- CONSUELO LORENZO (Corresponding author), EUGENIA C. SÁNTIZ and JORGE ity (Erlinge et al., ; Daniel et al., ; Bailey, ) and BOLAÑOS-CITALÁN Departamento de Conservación de la Biodiversidad, El Colegio de La Frontera Sur, Unidad San Cristóbal, Carretera Panamericana y can cause population fluctuations in response to environ- Periférico Sur s/n, Barrio de María Auxiliadora, C.P. 29290, San Cristóbal de mental changes and the amount and quality of available Las Casas, Chiapas, México. E-mail [email protected] food (Keith & Windberg, ; Keith, ). Therefore, DARÍO NAVARRETE-GUTIÉRREZ Laboratorio de Información Geográfica, El Colegio identifying the impact of changes in vegetative cover and de La Frontera Sur, Unidad San Cristóbal, San Cristóbal de Las Casas, Chiapas, México land use on distribution and population fluctuations of Received  August . Revision requested  February . mammals, using basic ecological parameters such as popu- Accepted  April . First published online  June . lation abundance and density, facilitates decision making

Oryx, 2019, 53(2), 321–328 © 2017 Fauna & Flora International doi:10.1017/S0030605317000485 Downloaded from https://www.cambridge.org/core. IP address: 170.106.35.234, on 28 Sep 2021 at 00:40:01, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605317000485 322 C. Lorenzo et al.

for the conservation of endemic and threatened mammal turn to subsistence hunting, which has a negative effect on species, such as L. flavigularis, as well as adequate manage- populations of lagomorphs, mainly L. flavigularis.Grey ment of agriculture and other land-based economic foxes and coyotes are also hunted, although not on a regular activities. basis (J. Antonio, pers. comm.). − Densities of – individuals km have been reported for L. flavigularis (Lorenzo et al., ; Vargas, ; Methods Sántiz, ), and abrupt changes in density have been recorded over  years of monitoring. These changes have been Surveys partially attributed to management practices such as pre-  scribed burning and grazing (Lorenzo et al., ). The population density of L. flavigularis, S. floridanus and Given the importance for wildlife management and con- the carnivores U. cinereoargenteus and C. latrans was esti- servation of identifying long-term fluctuations in the popu- mated annually during at least  month in the dry season lation density of lagomorphs, the relationship of these (November–April) and  month in the rainy season fluctuations to those of carnivores, and the responses of (May–October) over  years (–). As there were lagomorph population densities to changes in vegetative few sightings of U. cinereoargenteus and C. latrans, these cover and land use (such as grazing and prescribed burn- were grouped together as carnivores. We used the line tran- ing), the objective of this study was to examine the relation- sect method (Buckland et al., ) to monitor mammal spe- ships between fluctuations in population densities of cies along an  km transect of variable width between mammals (L. flavigularis, S. floridanus, and their natural Montecillo Santa Cruz and Huamuchil. This transect was predators U. cinereoargenteus and C. latrans) and changes established according to accessibility (traversable roads)  in land use and vegetative cover over a -year period. and visibility (flat open areas) (Fig. ). Number of individuals was recorded while travelling along the transect in a – Study area pickup truck at km per hour, at night, using halogen lanterns for illumination. Geographical location, altitude, Land use and vegetative cover were analysed in four muni- habitat type, and perpendicular distance (the shortest dis- cipalities in the southern region of the Isthmus of tance from the individual to the transect, in m; Buckland Tehuantepec in the Mexican state of Oaxaca: et al., ) were recorded for each individual observed. San Francisco del Mar, San Francisco Ixhuatán, San The perpendicular distance was recorded for jackrabbits Dionisio del Mar, and Juchitán de Zaragoza. Mammals and cottontail rabbits since , and for carnivores since were monitored in Montecillo Santa Cruz in the municipal- . For this, an electronic distance measuring device ity of San Francisco del Mar, and Huamuchil in the muni- (Bushnell Yardage Pro, Bushnell Corporation, Overland cipality of San Dionisio del Mar (Fig. ). The study area Park, USA) was used. All surveys were conducted during  comprised . km and the area surveyed for mammals .–., when lagomorphs and carnivores are most ac-  was . km . Climate is warm sub-humid, with a mean an- tive (Carrillo-Reyes et al., ; Rioja et al., ). Each night, nual temperature of °C, and mean total annual precipita- the same  km transect was travelled in both directions, at tion of . mm (García, ). least  hours apart to avoid duplicating data (in number of Residents of Montecillo Santa Cruz are traditional fish- records and kilometers travelled); each mammal observed ers, although over the past decade they have begun to was recorded, and density was estimated using these data. plant sorghum for sale and use as fodder for livestock, Data were analysed using Distance . (Buckland et al., and maize and watermelon for family consumption ) to estimate density for each mammal species, and (Vargas, ; Sántiz et al., ). Cattle are raised extensive- we considered each direction travelled along the transect ly in all grassland areas, and prescribed burning is carried to be independent (i.e. we analysed the data for each direc- out to promote regeneration of grasses (Lorenzo et al., tion independently). To evaluate the probability of detecting , ; Vargas, ). animals, the four models used by Distance were tested: half- Within the study area a sand bar connects the Inferior normal, uniform, hazard rate, and negative exponential. Lagoon with the Gulf of Tehuantepec (Fig. ). The sand Each model varies depending on homogeneity of sightings, bar closes and opens cyclically, changing in length as a result probability of detecting individuals according to the dis- of natural events (e.g. changes in sea level, hurricanes). This tance from which they are observed, and number of sight- process affects local people’s socio-economic activities, as ings (Buckland et al., ). In each case a cosine they principally engage in fishing. When the sand bar is adjustment was assessed using likelihood ratio tests. The closed, movement of fish and nutrients from the Gulf of longest % of the perpendicular distances recorded through- Tehuantepec to the Inferior Lagoon is inhibited, and fish out the analyses were eliminated to avoid bias introduced by and shrimp populations decrease, and therefore local people atypical outlier distance sightings. The final model was

FIG. 1 Study area in Montecillo Santa Cruz, south-eastern Oaxaca, Mexico, in which vegetative cover and land use were analysed, with the location of an  km transect between Montecillo and Huamuchil along which lagomorphs and carnivores were monitored during – .

chosen based on a combination of the lowest value for Akaike’s information criterion (AIC) and the lowest vari- ance (Rizo-Aguilar et al., ) for each year of monitoring. The population density obtained corresponds to the area  monitored for mammals (. km ; i.e. the length of the transect ( km) multiplied by the maximum perpendicular distance ( m each side of the transect) at which it is possible to identify observed animals). The results obtained for the  density in the monitoring area (. km ) were extrapolated  to the total study area (. km ). FIG. 2 Fluctuations in population densities of the Tehuantepec jackrabbit Lepus flavigularis, the eastern cottontail Sylvilagus Changes in vegetative cover and land use floridanus, and carnivores (Canis latrans and Urocyon cinereoargenteus) in Montecillo Santa Cruz, Municipality Maps of vegetation and land use were created using analysis San Francisco del Mar, and Huamuchil, Municipality San Dionisio del Mar, Oaxaca, Mexico (Fig. ) during –, of a  satellite image, from the Landsat Enhanced  with years indicated in which the sand bar was closed and in Thematic Mapper (ETM+), and a image from the which there was extensive burning. Landsat Operational Land Imager (OLI). Changes in vegetative cover and land use were processed using the inter- dependent classification method (FAO, ), stratifying correctly or incorrectly from satellite images (Velázquez the two scenes with ArcGIS . (ESRI, Redlands, USA). et al., ). For these points, types of vegetation and land Using this approach we delimited polygons for each type use were described. of vegetation and land use, to avoid bias in delimiting Once vegetation and land-use maps were drawn up for each thematic class. Estimating changes in surface area  and , along with the road layer and the digital ele- also involved the road layer, taken from a  base map, vation model, rates of change were estimated using the tran- using ArcGis ., and the digital elevation model of sition matrices (Bocco et al., ) by superimposing maps Instituto Nacional de Estadística y Geografía (for , using the Land Change Modeler module of IDRISI Selva with  m resolution). v. . (Clark Labs, Worcester, USA). An equation pro- To verify classification of the satellite image and ensure posed by the FAO () was used to obtain rates of percent- reliability of vegetative cover and land-use maps,  control age change in surface area for each type of vegetation and points were recorded using a global positioning system in land use. This procedure was applied to all types of vegeta- sites where the vegetation could potentially be interpreted tion and land use: human-induced grassland, savannah,

TABLE 1 Percentage change (δ) in surface area (ha) for each type of vegetation and land use in Montecillo Santa Cruz, Oaxaca, Mexico (Fig. ), in  and , with the change in area (ha), the percentage lost or gained, and the change per year (ha).

Types of vegetative cover and Surface area (ha) Change in % loss Change per land use 2001 2014 δ (%) area (ha) or gain year (ha) Human-induced grassland 6,806.5 6,804.8 −0.002 −1.710 −0.03 −0.13 Savannah 8,174.5 6,823.4 −1.4 −1351.2 −16.5 −103.94 Seasonal agriculture 3,087.1 3,842.9 1.8 755.8 24.5 58.14 Human settlements 202.1 255.9 1.9 53.7 26.6 4.13 Tropical dry forest 6,474.9 5,961.4 −0.7 −513.5 −7.9 −39.50 Burned area 957.2 2,323.5 7.4 1366.4 142.8 105.11 Areas without vegetation 833.7 1,152.7 7.4 319.1 38.3 24.54 Secondary forest 5,721.8 5,533.8 2.6 −187.9 −3.3 −14.46 Bodies of water 28,895.2 28,531.4 −0.3 −363.8 −1.3 −27.98 Mangrove swamp 3,399.9 3,323.0 −0.1 −76.9 −2.3 −5.92

seasonal agriculture, human settlements, tropical dry forest, with an annual loss of .%, and an increase in burned areas, areas without vegetation, secondary forest, human-induced grassland (. ha) and burned areas bodies of water, and mangrove swamps. The results describe (. ha; Table ). transitions from one type of land cover to another through- From  to  seasonal agriculture, human settle- out the region (Velázquez et al., ). ments, burned areas and areas without vegetation showed annual increases in surface area. Burned areas increased by .% annually, with a total increase of ,. ha Results (.%). During the same time period, areas without vege-   In Montecillo Santa Cruz the mean estimated density of tation increased by . % annually, with a total increase of      L. flavigularis during – was . ± SE . . ha ( . %; Table ). Burned areas were located mainly      individuals per km (range .–.; model hazard rate/ in savannahs ( , . ha), human-induced grasslands (    cosine; AIC = .;CV=.%) and of S. floridanus . ± ha), and forests ( . ha; Table ). All changes (losses  SE . individuals per km (range .–.; model hazard and increases) in land use and surface area of vegetative    rate/cosine; AIC = .;CV=.%). The mean estimated cover from to are shown in Fig. . density of the carnivores U. cinereoargenteus and C. latrans –   ±    during was . SE . individuals per km Discussion (range .–.; model hazard rate/cosine; AIC = .; CV = .%). The total sampling effort (for all  years) The estimated population density of L. flavigularis (. in- − was  km travelled for L. flavigularis and S. floridanus, dividuals km ) in the study region is similar to estimates − and  km travelled for the carnivores. from previous studies (.–. individuals km ; Vargas, Fluctuations in mean annual population density for each ; Sántiz, ; Lorenzo et al., ). However, mean mammal species/group are shown in Fig. . Although sev- densities of L. flavigularis are low compared to other lago- eral fluctuations occurred during –, as a general morph species, such as Lepus californicus (– indivi- − trend the density of L. flavigularis indicates a general de- duals km ; Hayden, ; Davis & Schmidly, ; cline; Sylvilagus floridanus has also declined but appears Portales-Betancourt et al., ). The estimated population to be stable since ; and carnivores tended towards sta- density for S. floridanus in this study (. individuals − bility throughout the study period (Fig. ). km ) is also low compared to other studies of the same spe- − Savannah (,. ha in ; ,. ha in ) and cies (.–, individuals km ; Chapman et al., ; human-induced grassland (,. ha in ; ,. ha Silvano et al., ). Alteration and degradation of lago- in ) were the dominant cover types in the study area morph habitat has probably led to a decrease in available (Table ), accounting for . and .% of total surface food and space over time, resulting in lower population area on average, respectively. Almost all vegetative cover densities (Lorenzo et al., ; Sántiz, ). types showed losses in surface area from  to , but The density of L. flavigularis decreased drastically over the most drastic loss occurred in savannah, with a .% de- the study period, whereas the density of S. floridanus decrease annually, and a total loss of ,. ha (.%) of the creased significantly only during –. Highs and original surface area. This was principally a result of fires lows in densities of the two species (Fig. ) did not overlap (burned area = ,. ha) and an increase in agricultural except in – and ; this may be explained by the areas ( ha). Tropical dry forest lost . ha (.%), differential response of the two species to habitat use and

food availability. Lepus flavigularis inhabits savannahs and human-induced grasslands (Lorenzo et al., ; Carrillo-Reyes et al., ; Sántiz et al., ) and feeds mainly on grasses (Lorenzo et al., ), whereas S. florida- Mangrove swamp, ha (%) nus inhabits human-induced grasslands, tropical forests, and scrub-brush, feeding on herbaceous and woody plants (Chapman et al., ; Chapman & Ceballos, ). It is likely that the two species avoid competing with each other.

Bodies of water, ha (%) The combined population density of the carnivores U. cinereoargenteus and C. latrans was stable over time. These species are adapted to a range of environments and can tra- vel long distances in search of food, without excessive en- ergy expenditure (Villa & Cervantes, ). In our study Secondary forest, ha (%)

. area, at least, they do not appear to be greatly affected by changes in land cover.  – In the study area, burned areas, areas without vegetation,

 and human settlements increased in surface area from  to . Undisturbed land has been converted to agriculture, 37.17 (1.1) Areas without vegetation, ha (%) with an increase in surface area of . ha during this per- ), during  iod. This land was initially planted with corn; however, as a

Fig. result of changes in geographical and environmental condi- tions (sandy soil, drought and intense rainfall), cultivation of sorghum has increased since  (Vargas, ; Burned area, ha (%) Lorenzo et al., ; Rioja-Paradela et al., ). Savannahs and forests have increasingly been converted to pastures for livestock raising (Lorenzo et al., ; Rioja-Paradela et al., ), affecting the coverage and diver- sity of vegetation (Altesor et al., ). Trampling by cattle Tropical dry forest, ha (%) modifies the soil’s physical properties, causing it to lose its capacity for water retention, thereby facilitating erosion (Drewry & Paton, ). It has been observed that the per- manence of the height and cover of species of bunchgrass Human settlements, ha (%) such as Muhlenbergia macroura and Jarava ichu benefits the presence and abundance of other threatened lagomorph species, such as the volcano rabbit Romerolagus diazi, be- cause it provides refuge from potential predators and nest- ing (Hoth et al., ; Rizo-Aguilar et al., ). 246.24 (3.6) 1.98 (0.03) 286.02 (4.2) 2.7 (0.04) 190.53 (2.8) 9.72 (0.1) Seasonal agriculture, ha (%) To manage grazing areas, residents of Montecillo Santa Cruz carry out prescribed burning, which consists of delib- erately causing fires to promote regeneration of grasslands during the dry season. However, these fires frequently be- Savannah, ha (%) come uncontrolled, affecting large areas of land (Lorenzo et al., , ; Vargas, ). Changes in land use to accommodate agriculture, including prescribed burning, have been the main cause of de- struction of large areas of savannah (.% of the original surface area), which is the preferred habitat of L. flavigularis. 33.48 (4.0) 0.09 (0.01) 2.07 (0.2) 70.02 (8.4) Modified to: Human-induced grassland, ha (%) This is a significant threat to this Endangered species, as lagomorphs are unable to quickly recolonize intensively burned areas (Meslow & Keith, ; Driessen, ; Salvatori et al., ). The time it takes for lagomorphs to

2 Change in area (ha) from one type of vegetation and land use to another in Montecillo, Oaxaca, Mexico ( recolonize these areas depends on how long it takes for habitat to recover its capacity to provide them with sufficient vegetation grassland ABLE

SavannahSeasonal agricultureHuman 14.94 settlements (0.5)Tropical dry forestBurned area 11.25 238.77 (0.1) (3.7)Areas without Secondary forest 88.11 (9.2) 22.95Bodies (0.4) of water 263.25Mangrove (4.6) swamp 82.17 (1.3) 61.92 23.76 (1.8) (0.1) 69.75 (7.3) 301.95 0.63 (3.7) (0.01) 25.74 (2.7) 524.43 (9.2) 15.93 16.74 (0.28) (0.54) 1.08 (0.03) 3.24 (0.01) 8.82 64.08 (0.11) (6.69) 10.44 (0.3) 19.08 1024.11 (0.07) (12.5) 190.89 (2.9) 178.74 (3.1) 2.97 (0.05) 384.75 (12.5) 98.37 (1.2) 46.17 (0.7) 6.57 (0.1) 381.87 76.14 (1.3) (8.0) 22.14 (0.08) Human-induced T food and protection (Parker, ), and burning results in

FIG. 3 Vegetative cover and land use in the municipalities of San Dionisio del Mar, San Francisco del Mar, San Francisco Ixhuatán, and Juchitán de Zaragoza, Oaxaca, Mexico, in (a)  and (b) .

temporary habitat fragmentation, which could affect popu- habitat. Such a programme could be certified as a Wildlife lation densities of several species (Fahrig & Paloheimo, ; Use and Management Unit by the Department of the Diffendorfer et al., ; Klok & De Roos, ). Our find- Environment and Natural Resources, to obtain legal use per- ings support this observation, as the population density of mits for a threatened mammal species, and economic sup- L. flavigularis decreased in , when burned areas in- port for programme development. () As part of the creased (Fig. ). However, fires have had a positive effect Wildlife Use and Management Unit a Communal on the abundance of R. diazi, as they maintain and promote Ecological Reserve could be established, to be administrated new growth of the dominant zacaton bunchgrass, the main by community authorities, with universities playing a tech- food source for this rabbit (Hunter & Cresswell, ). nical advisory role. Local protected areas have been shown Additionally, the closing of the sand bar affects lagomorph to promote appropriation of territory by communities, and population density. The sand bar closed in  and , the patrimony of natural resources, and their management and the following years the mean population density of could be a viable method of conserving habitat and the − L. flavigularis decreased (from . individuals km in Tehuantepec jackrabbit, as well as improving the quality −  to . individuals km in , and from . indivi- of life of local residents. This could ensure the persistence − − duals km in  to . individuals km in ). This of the Tehuantepec jackrabbit, with economic support process appears to be affecting survival of the species, al- from the government. though the sand bar remained open in  and  and the population recovered slightly. Acknowledgements Conservation and management strategies We thank Miguel Aquino, Roberto Gutiérrez, Leyberto We offer several recommendations to conserve L. flavigularis Gutiérrez, Juan Antonio, Julieta Vargas, Felipe Barragán, and establish appropriate management strategies for grass- and the people of the municipality of San Francisco del land and savannah communities. () Grasses should be con- Mar for their valuable help during fieldwork, Ann trolled annually by fire, taking care that fire does not spread Greenberg for editorial support, and the families of beyond targeted areas. () Livestock-raising practices should Antonio Gutiérrez and Gutiérrez Vázquez for housing our be improved to avoid a negative impact on grasses; for ex- crew. We thank El Colegio de la Frontera Sur, the Chicago ample, by periodically rotating cattle among pastures to Zoological Society, the Lincoln Park Zoo Neotropic Fund, avoid overgrazing, thereby facilitating recovery of grasses and Mexico’s Consejo Nacional de Ciencia y Tecnología, to increase their vegetative cover and fodder productivity. and Secretaría de Medio Ambiente y Recursos Naturales () A programme of reproduction in semi-captivity in situ for funding this research. Recommendations and comments in protected enclosures should be developed. If successful, from Martin Fisher and an anonymous reviewer improved jackrabbits could be released and reintroduced into the this article.

Author contributions DAVIS,B.&SCHMIDLY, D.J. () Black-tailed jackrabbit. In The Mammals of Texas – Online Edition. Texas Tech University. Http:// CL has provided funding for this study since . She has www.nsrl.ttu.edu/tmot/Default.htm [accessed  April ].  monitored mammals in the field since , and managed DIFFENDORFER, J.E., GAINES, M.S. & HOLT, R.D. ( ) Habitat fragmentation and movements of three small mammals (Sigmodon, the mammal database. She supported the analysis of popu- Microtus and Peromyscus). Ecology, , –. lation density, and was the principal author. ECS has been DREWRY, J.J. & PATON, R.J. () Effects of cattle treading and monitoring mammals in the field since . She managed natural amelioration on soil physical properties and pasture under the mammal database, reviewed satellite images and ana- dairy farming in Southland, New Zealand. New Zealand Journal of lysed changes in vegetation cover and land use, and assisted Agricultural Research, , –.  in writing the article. JBC has monitored mammals in the DRIESSEN,M.( ) Effects of fire on the broad-toothed mouse,  Mastacomys fuscus, and other small mammals in buttongrass field since . He managed the database, analysed density, moorlands of western Tasmania – preliminary findings. Conference and assisted in writing the article. DNG managed the data- proceedings. Australian Bushfire Conference, Albury, Australia. base, analysed changes in vegetative cover and land use, and ERLINGE, S., GÖRANSSON, G., HÖGSTEDT, G., JANSSON, G., LIBERG, assisted in writing the article. O., LOMAN, J. et al. () Can vertebrate predators regulate their prey? The American Naturalist, , –. FAHRIG,L.&PALOHEIMO,J.() Determinants of local population References size in patchy habitats. Theoretical Population Biology, , –. FAO (FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS) ALTESOR, A., OESTERHELD, M., LEONI, E., LEZAMA,F.&RODRÍGUEZ, () Forest resources assessment . Survey of tropical forest C. () Effect of grazing on community structure and productivity cover and study of change processes. FAO Forestry Paper, .FAO, of a Uruguayan grassland. Plant Ecology, , –. Rome, Italy. ANDERSON,S.&GAUNT,A.() A classification of the white-sided GARCÍA,E.() Modificaciones al sistema de clasificación climática jack rabbits of Mexico. American Museum Novitates, , –. de Köppen (para adaptarlo a las condiciones de la República ARRIAGA,L.&GÓMEZ,L.() Posibles efectos del cambio climático Mexicana). Instituto de Geografía, Universidad Nacional Autónoma en algunos componentes de la biodiversidad de México. In Cambio México, Mexico City, Mexico. Climático: una visión desde México (eds J. Martínez & GONZÁLEZ, P.G., BRIONES-SALAS,M.&ALFARO, A.M. () A. Fernández), pp. –. INE/SEMARNAT, Mexico. Integración del conocimiento faunístico del estado. In Biodiversidad BAILEY,T.() Peninsula Snowshoe Hares on the Decline. Kenai de Oaxaca (eds A.J. García-Mendoza, M.J. Ordóñez & National Wildlife Refuge. Refuge Notebook. U.S. Fish and Wildlife M. Briones-Salas), pp. –. Instituto de Biología, Service, Alaska, USA. UNAM-Fondo Oaxaqueño para la Conservación de la Naturaleza– BENDER, D.J., CONTRERAS, T.A. & FAHRIG,L.() Habitat loss and World Wildlife Fund, Mexico. population decline: a meta-analysis of the patch size effect. Ecology, HAYDEN,P.() Seasonal occurrence of jackrabbits on Jackass Flat, , –. Nevada. The Journal of Wildlife Management, , –. BOCCO, G.M., MENDOZA,E.&MASERA,O.() La dinámica del HOTH, J., VELAZQUEZ, A., ROMERO, F.J., LEON, L., ARANDA,M.& cambio del uso del suelo en Michoacán. Una propuesta BELL, D.J. () The volcano rabbit—a shrinking distribution and a metodológica para el estudio de los procesos de deforestación. threatened habitat. Oryx, , –. Boletín Investigaciones Geográficas, , –. HUNTER,M.&CRESSWELL,W.() Factors affecting the BUCKLAND, S.T., REXSTAD, E.A., MARQUES, T.A. & OEDEKOVEN, C.S. distribution and abundance of the Endangered volcano rabbit () Distance Sampling: Methods and Applications. Springer, Romerolagus diazi on the Iztaccihuatl volcano, Mexico. Oryx, , Heidelberg, Germany. –. CARRILLO-REYES, A., LORENZO, C., NARANJO, E.J., PANDO,M.& INEGI (INSTITUTO NACIONAL DE ESTADÍSTICA Y GEOGRAFÍA) RIOJA,T.() Home range dynamics of the Tehuantepec () Carta de uso actual del suelo y vegetación. Serie III, Mexico. jackrabbit in Oaxaca, Mexico. Revista Mexicana de Biodiversidad, , INEGI (INSTITUTO NACIONAL DE ESTADÍSTICA Y GEOGRAFÍA) –. () Guía para la interpretación de cartografía. Uso del suelo y CERVANTES, F.A., LORENZO, C., FARÍAS,V.&VARGAS,J.() Lepus vegetación. Escala :. Series IV. Mexico. flavigularis.InThe IUCN Red List of Threatened Species : KEITH,L.() Dynamics of snowshoe hare populations. In Current e. TA. Http://dx.doi.org/./IUCN.UK..RLTS. Mammalogy (ed. H.H. Genoways), pp. –. Plenum Press, TA.en [accessed  April ]. New York, USA. CHAPMAN, J.A. & CEBALLOS,G.() The cottontails. In Rabbits, KEITH, L.B. & WINDBERG, L.A. () A demographic analysis of the Hares and Pikas, Status Survey and Conservation Action Plan (eds J. snowshoe hare cycle. Wildlife Monographs, , –. A. Chapman & J.E.C. Flux), pp. –. IUCN/SSC Lagomorph KLOK,C.&DE ROOS, A.M. () Effects of habitat size and quality on Specialist Group, Oxford, UK. equilibrium density and extinction time of Sorex araneus CHAPMAN, J.A., HOCKMAN,J.&EDWARDS,W.() Cottontails populations. Journal of Animal Ecology, , –. (Sylvilagus floridanus) and allies. In Wild Mammals of North LÓPEZ, J.A., LORENZO,C.,BARRAGÁN,F.&BOLAÑOS,J.() America (eds J.A. Chapman & G.A. Feldhamer), pp. –. Johns Mamíferos terrestres de la zona lagunar del Istmo de Hopkins University Press, Baltimore, USA. Tehuantepec, Oaxaca, México. Revista Mexicana de CHAPMAN, J.A., HOCKMAN, J.G. & OJEDA, C.M.M. () Sylvilagus Biodiversidad, , –. floridanus. Mammalian Species, , –. LÓPEZ-GRANADOS, E., MENDOZA,M.&ACOSTA,A.() Cambio DANIEL, A., HOLECHEK, J., VALDEZ, R., TEMBO, A., SAIWANA, L., de cobertura vegetal y uso de la tierra. El caso de la cuenca endorreica FUSCO,M.&CARDENAS,M.() Jackrabbit densities on fair and del lago de Cuitzeo, Michoacán. Gaceta Ecológica, , –. good condition Chihuahuan desert range. Journal of Range LORENZO, C., CERVANTES, F.A., BARRAGÁN,F.&VARGAS,J.() Management, , –. New records of the endangered Tehuantepec jackrabbit (Lepus

flavigularis) from Oaxaca, Mexico. The Southwestern Naturalist, , RIZO-AGUILAR, A., GUERRERO, J.A. HIDALGO-MIHART, M.G. & –. GONZÁLEZ-ROMERO,A.() Relationship between the LORENZO, C., CARRILLO-REYES, A., GÓMEZ-SÁNCHEZ, M., abundance of the Endangered volcano rabbit Romerolagus diazi and VELÁZQUEZ,A.&ESPINOZA,E.() Diet of the endangered vegetation structure in the Sierra Chichinautzin mountain range, Tehuantepec jackrabbit, Lepus flavigularis. Therya, , –. Mexico. Oryx, , –. LORENZO, C., CARRILLO-REYES,A.,RIOJA-PARADELA, T.M., DE LA RZEDOWSKI,J.() Vegetación de México. Comisión Nacional para PAZ-CUEVAS,M.,BOLAÑOS-CITALÁN,J.&ÁLVAREZ-CASTAÑEDA, el Conocimiento y Uso de la Biodiversidad, Mexico. S.T. () Estado actual de conservación de liebres y conejos en SALVATORI, V., EGUNYU, F., SKIDMORE, A.K., DE LEEUW,J.&VAN categoría de riesgo en México. Technical Report. Project HK. GILS, H.A.M. () The effects of fire and grazing pressure Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, on vegetation cover and small mammal populations in the Mexico City, Mexico. Maasai Mara National Reserve. African Journal Ecology, LORENZO, C., RETANA-GUIASCON, O., CERVANTES, F.A., VARGAS,J. , –. &PORTALES, G.L. () Status Survey of the Critically Endangered SÁNTIZ, E.C. () Distribución y abundancia de la liebre endémica Lepus flavigularis. Final report to Chicago Zoological Society, El Lepus flavigularis y el conejo castellano Sylvilagus floridanus Colegio de la Frontera Sur. San Cristóbal de Las Casas, Chiapas, (Mammalia: Lagomorpha) en el Istmo de Tehuantepec. Oaxaca, Mexico. México. Undergraduate thesis. Universidad de Ciencias y Artes de LORENZO, C., RIOJA, T.M., CARRILLO,A.&CERVANTES, F.A. () Chiapas, Mexico. Population fluctuations of Lepus flavigularis (Lagomorpha: SÁNTIZ, E.C., GONZÁLEZ-ROMERO, A., LORENZO, C., Leporidae) at Tehuantepec Isthmus, Oaxaca, Mexico. Acta GALLINA-TESSARO,S.&CERVANTES, F.A. () Uso y selección Zoológica Mexicana, , –. de asociaciones vegetales por la liebre de Tehuantepec (Lepus MAS, J.F., VELÁZQUEZ,A.&COUTURIER,S.() La evaluación de flavigularis) en Oaxaca, México. Therya, , –. los cambios de cobertura/uso del suelo en la República Mexicana. SÁNTIZ, E.C., LORENZO, C., CARRILLO-REYES, A., NAVARRETE, D.A. Investigación Ambiental, , –. &ISLEBE,G.() Effect of climate change on the distribution of a MESLOW, E.C. & KEITH, L.B. () Demographic parameters of a critically threatened species. Therya, , –. snowshoe hare population. The Journal of Wildlife Management, , SILVANO, F., ACQUARONE,C.&CUCCO,M.() Distribution of the –. eastern cottontail Sylvilagus floridanus in the province of NÁJERA, O., BOJÓRQUEZ, J.I., CIFUENTES, J.L. & MARCELEÑO,S. Alessandria. Hystrix, , –. () Cambio de cobertura y uso del suelo en la cuenca del río TORRES-COLÍN,R.() Tipos de vegetación. In Biodiversidad de Mololoa, Nayarit. Revista Biociencias, , –. Oaxaca (eds A.J. García-Mendoza, M.J. Ordóñez & ORTIZ, P., HERNÁNDEZ, J.R. & FIGUEROA, J.M. () M. Briones-Salas), pp. –. Instituto de Biología, UNAM, Fondo Reconocimiento Fisiográfico y geomorfológico. In Biodiversidad de Oaxaqueño para la Conservación de la Naturaleza–World Wildlife Oaxaca (eds A.J. García-Mendoza, M.J. Ordóñez & Fund, Mexico City, Mexico. M. Briones-Salas), pp. –. Instituto de Biología, UNAM-Fondo VARGAS,J.() Distribución, abundancia y hábitat de la liebre Oaxaqueño para la Conservación de la Naturaleza–World Wildlife endémica Lepus flavigularis (Mammalia: Lagomorpha). MSc thesis. Fund, Mexico. Universidad Nacional Autónoma de México, Mexico. PARKER, G.R. () Use of spruce plantations by snowshoe hare in VARGAS,Z.() Valoración de los vertebrados terrestres por huaves y New Brunswick. The Forestry Chronicle, , –. zapotecas del Istmo de Tehuantepec, Oaxaca, México. MSc thesis. PERALTA-RIVERO, C., CONTRERAS-SERVÍN, C., El Colegio de la Frontera Sur, San Cristóbal de Las Casas, Chiapas, GALINDO-MENDOZA, M.G., MAS CAUSSEL, J.F. & Mexico. ALGARA-SILLER,M.() Analysis of land use and land cover VELÁZQUEZ, A., MAS, J.F., PALACIO, J.L., DÍAZ, J.R., MAYORGA, S.R., changes and evaluation of natural generation and potential ALCÁNTARA, C. et al. () Patrones y tasas de cambio de uso del restoration areas in the Mexican Huasteca region. Open Journal of suelo en México. Gaceta Ecológica INE-SEMARNAT, , –. Forestry, , –. VILLA, R.B. & CERVANTES, F.A. () Los Mamíferos de México. PORTALES-BETANCOURT, G., HERNÁNDEZ, L., LAUNDRÉ,J.& Instituto de Biología, Universidad Nacional Autónoma de Mexico CERVANTES, F.A. () Reproducción y densidad de la liebre and Grupo Editorial Iberoamérica, Mexico. cola-negra (Lepus californicus) en relación a factores ambientales, en la Reserva de la Biosfera Mapimí, Desierto Chihuahuense. Therya, , –. Biographical sketches RIOJA, T., LORENZO, C., NARANJO, E., SCOTT,L.&CARRILLO-REYES, A. () Breeding and parental care in the endangered Tehuantepec CONSUELO LORENZO is interested in the molecular systematics, jackrabbit (Lepus flavigularis). Western North American Naturalist, taxonomy and conservation of lagomorphs and tropical rodents , –. and has been monitoring populations and habitat of the RIOJA-PARADELA, T., CARRILLO-REYES,A.&LORENZO,C.() Tehuantepec jackrabbit Lepus flavigularis for  years. EUGENIA Análisis de población viable para determinar el riesgo de extinción SÁNTIZ studies the ecology and effects of global climate change on de la liebre de Tehuantepec (Lepus flavigularis) en Santa María del the distribution of threatened mammals, and the conservation and Mar, Oaxaca. Therya, , –. management of the Tehuantepec jackrabbit and its habitat. JORGE RIZO-AGUILAR, A., DELFÍN-ALONSO, C., GONZÁLEZ-ROMERO,A.& BOLAÑOS-CITALÁN’s work is focused on the conservation and GUERRERO, J.A. () Distribution and density of the zacatuche management of tropical mammals, especially bats and rodents. rabbit (Romerolagus diazi) at the Protected Natural Area “Corredor DARÍO NAVARRETE-GUTIÉRREZ studies changes in distribution of Biológico Chichinautizin”. Therya, , –. mammals, as well as consequences of land-use changes.