Population Size and Dynamics of the Lima Leaf-Toed Gecko, Phyllodactylus sentosus, in One of Its Last Refuges

Abstract

The Peruvian endemic Lima Leaf-Toed Gecko (Phyllodactylus sentosus) is a critically endangered species with just a few known localities of occurrence, which are isolated from each other, within Lima City and in the Ica region. During 1 yr, we carried out monthly evaluations to determine the influence of the environmental factors on the size and population dynamics of this species in the Huaca Pucllana, as this area maintains one of the largest populations in Lima. We took body measurements and reproductive data and made a total of 1,924 captures and recaptures. The low catchability during the coldest months caused a population underestimation in which adults fluctuated between 69 and 313 and juveniles between 88 and 351 throughout the year for the study area of 6.07 ha. The catchability increased in the warmest months when the adult population peaked between December and January, whereas the population of juveniles peaked in December and April. We noted sexual dimorphism, the females being 8% longer than males. The reproductive cycle seems more similar to that of other species that inhabit the temperate zones, where females have oviductal eggs in spring and the appearance of young individuals occurs in mid-to late summer when food is abundant. We recommend carrying out one evaluation per year in Huaca Pucllana and in the other localities of occurrence of these geckos during summertime. We also recommend carrying out a management program including the translocation of individuals between Huaca Pucllana and the other four closest localities.RESUMEN.-Los geckos de Lima (Phyllodactylus sentosus) son una especie ende ´mica del Per ´u y en peligro crı ´tico de extinci ´on, se les ha registrado en un bajo n ´umero de localidades de ocurrencia, aisladas entre sı ´, en la ciudad de Lima y en la regi ´on Ica. Realizamos evaluaciones mensuales para determinar la influencia de los factores ambientales en el taman ˜o y la dina ´mica poblacional de esta especie en la Huaca Pucllana a lo largo de un an ˜o, ya que esta localidad mantiene una de las poblaciones ma ´s grandes en Lima. Tomamos medidas corporales y datos reproductivos e hicimos un total de 1924 capturas y recapturas. La baja capturabilidad result ´o en la subestimaci ´on de la poblaci ´on los meses ma ´s frı ´os, con fluctuaciones entre 69 y 313 en adultos y entre 88 y 351 en juveniles, a lo largo del an ˜o, para el total de 6.07 ha del sitio de estudio. La capturabilidad increment ´o los meses ma ´s ca ´lidos donde la poblaci ´on adulta estimada alcanz ´o su ma ´ximo entre diciembre y enero, mientras que los juveniles mostraron un pico en diciembre y otro en abril. Se observ ´o dimorfismo sexual, siendo las hembras 8% ma ´s grandes que los machos. El ciclo reproductivo es similar al que presentan otras especies en zonas templadas donde las hembras tienen huevos oviductales en primavera, y la aparici ´on de individuos juveniles ocurre de mediados a finales del verano cuando la comida es abundante. Se recomienda realizar una evaluaci ´on anual en Huaca Pucllana y en ...

Population genomics reveals how 5 ka of human occupancy led the Lima leaf-toed gecko (Phyllodactylus sentosus) to the brink of extinction

“…4 A). The populations at the extremes of the geographical distribution of this species show the lowest migration rates, while those among the four largest census population size 16 – 18 (San Marcos, Parque de Las Leyendas, Pucllana and Mateo Salado: Fig. 4 , see Supplementary Table S3 online) were slightly higher, but still lower than 0.4, with exception of the populations of San Marcos and Parque de Las Leyendas that showed a high bidirectional gene flow with migration values of 0.99 and 1 (Fig.…”

“…1 ), which feature arid soil with scant vegetation and small rocks that resemble the natural habitat previous to human occupancy 11 . Nowadays, these areas are isolated from each other by completely urbanized areas in Lima, being estimated not to exceed the 500 adult individuals in huacas with the largest census population size 16 – 18 . Also, unlike other Phyllodactylus species, P. sentosus has low climbing abilities due to their toe structure, which reduces the probability of dispersion and escape from invasive local threats 15 .…”

Abundance and effect of health status on apparent survival of Guiana dolphins,Sotalia guianensis, in an open embayment in north‐eastern Brazil

“…Although capture has been widely used to estimate abundance, even recently (e.g. Kahn et al, 2019; Brown et al, 2020; Valdez et al, 2020), according to Cooch & White (2019), all the heterogeneity models in capture , except M bh , are not likelihood based. All eight Otis models can be modelled in program mark , with different estimators than used in capture .…”

“…Although CAPTURE has been widely used to estimate abundance, even recently (e.g. Kahn et al, 2019;Brown et al, 2020;Valdez et al, 2020), according to Cooch & White (2019), all the heterogeneity models in CAPTURE, except M bh , are not likelihood based.…”

Cities as sanctuaries

“…In addition, cities are at times the last remaining refuge for a species. A case in point is the Lima leaf-toed gecko (Phyllodactylus sentosus), a critically endangered species that is restricted to only several locations within the city of Lima, Peru (Valdez et al 2020). In contrast, cities may also be locations where previously undescribed species are discovered; for example, a new species of mud turtle (Kinosternon vogti) was recently identified in Puerto Vallarta, Mexico (López- Luna et al 2018), and a new species of leopard frog was found in New York City (Figure 1; Feinberg et al 2014).…”