Long‐term impact of protected colonial birds on a jeopardized cork oak population: conservation bias leads to restoration failure

Abstract

1. Conservation bias towards flagship species sometimes threatens other species of chief concern. Long-term studies of potential harm by favoured species on other sensitive species, though seldom adopted, are required to fairly evaluate the suitability of management and restoration efforts. 2. We illustrate the potential detrimental outcomes of conservation biased towards birds by investigating the long-term ) impact of a large waterbird colony (up to 13 000 pairs) on a remnant cork oak Quercus suber population at a World Biosphere Reserve in south-western Spain (the Doñana National Park). To this end, we compared changes in performance (growth, crown vigour and survival) of oaks occupied and unoccupied by the waterbird colony. 3. After 46 years of occupation, the risk of death to centenarian oaks in the area occupied by the colony was over twofold higher than for trees outside the area. Non-centenarian planted and naturally regenerated oaks showed similar trends, leading to restoration failure. 4. Synthesis and applications. Our long-term study reveals that waterbirds and centenarian oaks cannot coexist, at the most local scale, but they can at a regional scale including within the Doñana area. We propose immediate planting efforts in suitable colony-free areas, while managers evaluate the feasibility of relocating colonial waterbirds to an alternative location. To preserve the Doñana oak genetic pool, such reforestation should be accomplished using local seeds and seedlings. New trees should not be planted in close proximity of colony-occupied trees since it significantly reduces their survival. Doñana stakeholders should both overcome current conservation bias in favour of birds and enter into a process of settlement to best preserve the overall biodiversity of the system.

Assisting seed dispersers to restore oldfields: An individual‐based model of the interactions among badgers, foxes and Iberian pear trees

“…DisPear model code and parameter values are available from figshare https://doi.org/10.6084/m9.figshare.5280862.v1 (Fedriani, García, et al., ; Fedriani, Wiegand, et al., ).…”

Combined effects of seed provenance, plant facilitation and restoration site on revegetation success

“…We urge managers to accomplish our approach in revegetation actions of fragmented plant populations that have been rapidly and intensively disturbed by habitat destruction and other human activities. These would be the case, for example, of Q. suber , F. angustifolia and Juniperus macrocarpa populations in southern Spain (Fedriani et al., ; García‐Novo et al., ; López‐Pasarín, ), Chamaerops humilis and Ranunculus nodiflorus in France (Médail & Quézel, ; Noel, Porcher, Moret, & Machon ) and Fagus silvatica and C. humilis in Italy (Giovino, Scibetta, Saia, & Guarino ; Leonardi et al., ).…”

“…land‐use changes, timber exploitation, fires; Granados, Martín, & García Novo, ). To offset those and other detrimental effects (droughts, herbivory), several costly revegetation campaigns have been undertaken during the last few decades with intensive planting of the above mentioned tree species (Fedriani, García, Sanchéz, Calderon, & Ramo, ; García‐Novo, García, Carotenuto, Sevilla, & Faso, ; López‐Pasarín, ). However, such well‐intended revegetation campaigns have been largely unsuccessful (Fedriani et al., ) partly because they were not preceded by rigorous pilot experiments identifying the combination of conditions optimal for tree recruitment.…”

Population viability analyses in New Zealand: a review

“…Although most PVAs consider just a single species, it is important to be aware of ecosystem-level interactions if we are to avoid unintended and unwanted outcomes, such as the decline of non-target species or undesirable trophic interactions (Ruscoe et al 2011;Fedriani et al 2016). To avoid such unexpected or perverse outcomes it is important to consider the viability of not just the target species but also the ecosystem of which it is a component (Lindenmayer et al 2007).…”