One millennium of historical freshwater fish occurrence data for Portuguese rivers and streams

Abstract

The insights that historical evidence of human presence and man-made documents provide are unique. For example, using historical data may be critical to adequately understand the ecological requirements of species. However, historical information about freshwater species distribution remains largely a knowledge gap. In this Data Descriptor, we present the Portuguese Historical Fish Database (PHish–DB), a compilation of 2214 records (557 at the basin scale, 184 at the sub-basin scale and 1473 at the segment scale) resulting from a survey of 194 historical documents. The database was developed using a three-scale approach that maximises the inclusion of information by allowing different degrees of spatial acuity. PHish database contains records of 25 taxonomical groups and covers a time span of one millennium, from the 11th until the 20th century. This database has already proven useful for two scientific studies, and PHish further use will contribute to correctly assess the full range of conditions tolerated by species, by establishing adequate benchmark conditions, and/or to improve existing knowledge of the species distribution limits.

A Fish-Based Tool for the Quality Assessment of Portuguese Large Rivers

“…In that case, differences in abundance may not reflect differences in proximal habitat quality. However, we believe that this is not a relevant factor in our study, because historically these species abundantly occupied the habitat network along these rivers, including segments located many kilometres upstream of our study areas [71,72].…”

Fishing historical sources: a snapshot of 19th-century freshwater fauna in Spain

“…However, long-term fisheries datasets are rare and in general have a reduced spatial extent, informing about landings in specific spots. Mining historical sources is a promising approach to describe past species distributions and design conservation baselines and management efforts (Clavero and Hermoso 2015;Duarte et al 2018;Viana et al 2022). In Europe, geographic description initiatives have been developed at least since the eleventh century (Duarte et al 2018;Jones 2018), often in the form of geographic dictionaries (Clavero and Revilla 2014).…”

“…Mining historical sources is a promising approach to describe past species distributions and design conservation baselines and management efforts (Clavero and Hermoso 2015;Duarte et al 2018;Viana et al 2022). In Europe, geographic description initiatives have been developed at least since the eleventh century (Duarte et al 2018;Jones 2018), often in the form of geographic dictionaries (Clavero and Revilla 2014). Many of these historical documents provide information on natural resources, including vegetation and fauna, which can be used to describe past ecosystems and to identify conservation baselines (Clavero and Hermoso 2015;Viana et al 2022).…”

Occurrence of Atlantic salmon in the Douro River: Recent evidence

“…Wild salmon formerly occurred in several rivers draining the North of Portugal (Minho, Lima, Neiva, Cávado, Ave and Douro), reproducing in the rivers Minho, Lima and Douro, which are shared by Portugal and Spain (Valente et al, ; WWF, ; Figure ). Sparse mentions suggest the historical presence of the species farther South in the river Tagus (Duarte et al, ), but most references consider the river Douro as the original southern distribution limit for the species presence in Europe, and the Minho as the contemporary one (Parrish et al, ; Valente & Maia, ; Braña et al, ; Duarte et al, ; Jonsson & Jonsson, ). There are references listed in the Portuguese Historical Fish Database (Duarte et al, ) for the occurrence of salmon in the river Douro dated from 1610 to 1891.…”