Assessment of a terrestrial protected area for the conservation of freshwater biodiversity

Abstract

Freshwater ecosystems are essential to human well‐being and most have high biodiversity. However, this biodiversity has been suffering severe declines owing to the expansion of human activities. Protected areas (PAs) are essential for biodiversity conservation and have proved to be successful in stopping species extirpation if managed properly. Unfortunately, they are usually focused on terrestrial biodiversity, leaving freshwater ecosystems aside. The main goal of this study was to determine the influence of a PA (Montesinho Natural Park (MNP), Portugal) on freshwater biodiversity. Aquatic macroinvertebrates and fishes were surveyed, and biodiversity (richness, abundance, Shannon‐Wiener diversity, and Pielou's evenness) and water quality (IASPT) indices were calculated inside, at the periphery and outside the MNP. Results showed that the PA does not affect positively either water quality or the two faunal groups monitored. Macroinvertebrate communities were not influenced by the PA; however, the abundance of pearl mussel Margaritifera margaritifera was significantly higher and size was significantly lower inside the MNP. The richness and abundance of fish communities were significantly higher outside the MNP, except for trout Salmo trutta abundance which was higher inside the MNP. Given these results, the MNP does not guarantee the safeguard of overall aquatic biodiversity and habitats and we propose an extension of MNP to downstream areas in order to increase the number of species (mostly cyprinids) under legal protection. This work demonstrates that terrestrial PA planning and management should also consider aquatic biodiversity to achieve successful conservation.

Combined per‐capita and abundance effects of an invasive species on native invertebrate diversity and a key ecosystem process

“…In our sampled rivers, stream water characteristics were similar and indicated a very low human disturbance, as reported previously (Nogueira et al, 2021; Sousa et al., 2018, 2020), discarding the influence of water chemistry (or other environmental factors) on the observed effects and highlighting the negative impacts of the invasive signal crayfish on these ecosystems. The presence of P. leniusculus in both study rivers is relatively recent, nevertheless their effects were already detrimental for endangered species (e.g., Margaritifera margaritifera ; Sousa et al., 2019).…”

“…In our sampled rivers, stream water characteristics were similar and indicated a very low human disturbance, as reported previously (Nogueira et al, 2021;Sousa et al, 2018Sousa et al, , 2020, discarding the influ-…”

“…Pristine rivers, such as the ones where we ran our experiment (Nogueira et al, 2021), are expected to have high biodiversity and consequently high functional redundancy, making them more resistant and resilient to disturbances (Woodward, 2009). It is possible that the decrease in biodiversity imposed by crayfish did not lead to significant indirect effects on leaf breakdown as a result of functional redundancy.…”

“…In our manipulative experiment, we selected two rivers where the invasive crayfish P. leniusculus is currently spreading: Rabaçal and Tuela Rivers (Tua basin, NE Portugal). Rabaçal and Tuela Rivers have total lengths of 88 and 102 km, respectively, very low human disturbance, and similar climate regarding precipitation and temperature (Nogueira et al, 2021; Sousa et al., 2018, 2020). Within both rivers, the first specimens of P. leniusculus were detected in 2013 (Sousa et al., 2015) and since then the species has spread rapidly from upstream to downstream, presenting higher abundance at upstream (core) areas when compared to the invasion front (Sousa et al., 2019).…”

Predicting climatic threats to an endangered freshwater mussel in Europe: The need to account for fish hosts

“…Even though there was an increase of freshwater ecosystems that are somehow covered by protected areas since 1992, biodiversity loss in these systems has been increasing at an alarming rate (Acreman et al, 2019). Protected areas were typically designed for terrestrial ecosystems and opportunistically included freshwaters in some cases (Acreman et al, 2019;Dobler et al, 2018;Hermoso et al, 2014), disregarding the specific conservation challenges of aquatic biodiversity (Hermoso et al, 2015(Hermoso et al, , 2018Nogueira et al, 2021). The poor performance of protection of freshwater biodiversity for the next decades highlights the need for further effort to create new (or expand already existent) protected areas and make them more effective.…”