How does the beach ecosystem change without tourists during COVID-19 lockdown?

Urban tourist beach ecosystems provide the essential service of recreation. These ecosystems also support critical ecological functions where biodiversity conservation is not usually a priority. The sudden lockdown due to the COVID-19 pandemic created a unique opportunity to evaluate the effects of human absence in these urban-coastal ecosystems. This study examined bioindicators from 29 urban tourist beaches in seven Latin-American countries and assesses their response to lockdown about some relevant anthropogenic stressors such as pollution, noise, human activities, and user density. The presence of animals and plants, as well as the intensity of stressors, were assessed through a standardized protocol during lockdown conditions. Additionally, the environmental conditions of the beaches before and during lockdown were qualitatively compared using multivariate non-parametric statistics. We found notable positive changes in biological components and a clear decrease in human stressors on almost all the beaches. Dune vegetation increased on most sites. Similarly, high burrow densities of ghost crabs were observed on beaches, except those where cleaning activity persisted. Because of the lockdown, there was an exceptionally low frequency of beach users, which in turn reduced litter, noise and unnatural odors. The observed patterns suggest that tourist beaches can be restored to natural settings relatively quickly. We propose several indicators to measure changes in beaches once lockdown is relaxed. Adequate conservation strategies will render the recreational service of tourist beaches more environmental-friendly.

Abundance of Petrolisthes armatus (Crustacea: Porcellanidae) on a tropical estuarine intertidal rocky beach, Gulf of Nicoya estuary, Costa Rica.

Population of the porcellanid crab Petrolisthes armatus was studied on a rocky intertidal beach located at the Punta Morales peninsula in the mid upper Gulf of Nicoya estuary, Pacific coast of Costa Rica, from December 1997 to November 1998 (14 dates). Horizontal plankton tows (280 micron mesh net) were also made to verify the presence of P. armatus larvae. Crabs were collected every 3 m along three 18 m long transects, at two sites on the beach, by placing a bottomless bucket fringed with canvas to prevent the organisms from escaping under the rim. A total of 15,382 P. armatus were collected. Only 146 (0.95%) crabs had a carapace length longer than 10 mm, and 8995 (58.5%) were in the size range of 2 to 4.5 mm. The remaining crabs 6241 (40.5%) were in the size range of 4.6 to 10 mm. Male and female P. armatus were represented by 2777 and 3518 individuals respectively, with a sex ratio of 1:1.26. Ovigerous females were found at all dates and included 2937 individuals (83% of females). Plankton tows yielded only 73 larvae of P. armatus (Zoea 1), with a density of 1.2 larvae/m3. No statistically significant seasonal trends in the population of this species were detected. P. armatus appears to reproduce continuously the year around in Punta Morales, and some peaks of abundance were present during the dry and rainy seasons. These trends are similar to trends reported for other crustacean species in the Gulf of Nicoya.

Permanent genetic resources added to Molecular Ecology Resources Database 1 August 2010-30 September 2010.

This article documents the addition of 229 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acacia auriculiformis × Acacia mangium hybrid, Alabama argillacea, Anoplopoma fimbria, Aplochiton zebra, Brevicoryne brassicae, Bruguiera gymnorhiza, Bucorvus leadbeateri, Delphacodes detecta, Tumidagena minuta, Dictyostelium giganteum, Echinogammarus berilloni, Epimedium sagittatum, Fraxinus excelsior, Labeo chrysophekadion, Oncorhynchus clarki lewisi, Paratrechina longicornis, Phaeocystis antarctica, Pinus roxburghii and Potamilus capax. These loci were cross-tested on the following species: Acacia peregrinalis, Acacia crassicarpa, Bruguiera cylindrica, Delphacodes detecta, Tumidagena minuta, Dictyostelium macrocephalum, Dictyostelium discoideum, Dictyostelium purpureum, Dictyostelium mucoroides, Dictyostelium rosarium, Polysphondylium pallidum, Epimedium brevicornum, Epimedium koreanum, Epimedium pubescens, Epimedium wushanese and Fraxinus angustifolia.