Anthropogenic materials are a persistent pressure on ecosystems, affecting many species. Seabirds can collect these materials to construct their nests, which may modify nest characteristics and cause entanglement of chicks and adults, with possible consequences on breeding success. The incorporation of anthropogenic materials in nests of seabird species that breed in both natural and urban environments, such as gulls, is poorly known. Here, we characterize and compare anthropogenic materials incorporated in yellow-legged gull (Larus michahellis) nests from two natural and two urban breeding sites across their Portuguese breeding range and during 2 consecutive years. Anthropogenic materials were found in 2.6% and 15.4% of gull nests from natural locations and in 47.6% and 95.7% of nests from urban breeding sites. No differences were found on hatching success between urban and natural breeding colonies. A significantly higher number of anthropogenic materials were found in the largest and more populated urban breeding colony, which on average included items of a greater mass but smaller size than items from the other three colonies. The higher incorporation of anthropogenic materials in urban locations could be a consequence of a lower access to natural nest construction materials and higher availability of anthropogenic debris. The quantity and diversity of anthropogenic materials incorporated in gull nests from urban locations indicate a need for improved debris management in urban settlements.

The availability of suitable breeding habitats is an important factor in explaining seabird demographic fluctuations. For ground nesting seabirds, such as Little Terns (Sternula albifrons), an essential characteristic in determining suitability of breeding habitats is vegetative cover. This study evaluated whether the long-term fluctuations (1979–2014) in Little Tern breeding numbers on sandy beach colonies of Ria Formosa, Algarve, Portugal, could be explained by changes in vegetation cover at each sandy beach colony, environmental variability (measured by the climatic North Atlantic Oscillation index), or a combination of both. The percentage of vegetation cover for each sandy beach was calculated from aerial photos of Ria Formosa barrier islands from 1976 to 2012, and related to breeding census data from the same period. The climatic variation measured by the North Atlantic Oscillation index did not show a significant relationship with the number of breeding pairs nesting on each sandy beach c...

Biofertilizers are sustainable alternatives to mineral fertilizers in perennial crops, reducing the need for mineral inputs. This five-year field study evaluated three biofertilizers—Mycoshell^® (Glomus spp. + humic/fulvic acids), Kiplant iNmass^® (Azospirillum brasilense, Bacillus megaterium, and Saccharomyces cerevisiae), and Kiplant All-Grip^® (Bacillus megaterium and Pseudomonas spp.)—at different dosages alongside two mineral fertilizer regimes, T100 (full recommended dose) and T70 (70% of T100, alone or combined with biofertilizers), in an apple orchard under Mediterranean conditions. Biofertilizers maintained or increased soil nutrient availability by 5–15% and leaf N, P, K, Mg, and Zn concentrations by 5–12% compared with T100. Trees under biofertilizers, particularly Myc2 and Myc4, exhibited greater shoot growth (up to 30.4 m/year), trunk cross-sectional area (TCSA: 11.9 cm² in 2022), and canopy volume (2.21 m³), representing 10–20% increases. Selected biofertilizer treatments produced 6–7.5 kg/tree, 130–145 g average fruit weight, 66–74 mm diameter, 13.9–18.7 °Brix, and 13–18% dry matter, maintaining >90% of yield and fruit size relative to T100, with more balanced medium- and large-sized fruit distribution. Principal Component Analysis explained 66–72% of soil and leaf nutrient variance, confirming their multivariate impact. Overall, biofertilizers applied at recommended doses and timings can partially replace mineral fertilizers, sustaining productivity and quality, enhancing nutrient availability, and supporting long-term orchard sustainability. While climate remains the main driver of annual production, these findings provide evidence for integrating biofertilizers into environmentally friendly fertilization strategies.

Seabirds are hosts of several tick species, but there is little information on their infestation by soft ticks and pathogens they harbour is available. In this study, we evaluated soft tick infestation in gull chicks from two breeding colonies in Portugal and assessed the prevalence of anti-Borrelia antibody in adults gull and shearwaters from these colonies, as well as from two additional urban colonies. The prevalence of infestation by Ornithodorus maritimus ticks in gull chicks varied between (17.6 %) in three yellow legged gull (Larus michahellis) and 84.8 % in the Audouin's gull (Ichthyaetus audouinii), with a mean infestation intensity of 4.50 ticks per infested yellow-legged gull chick and 5.59 ticks per infested Audouin's gull chick. All ticks, except one, were at the larval stage. Infestation prevalence was significantly higher at Deserta Island (south Portugal) compared to Berlenga Island. Of the 133 ticks screened, only two tested positive for Borrelia: one for Borrelia turdi (from a yellow legged gull) and one Borrelia mayonii from a Audouin's gull. However, only one gene could be sequenced for each. No relapsing fever Borrelia species were detected. Although differences among colonies were only marginally significant, Deserta Island exhibited higher anti-Borrelia antibody prevalence than Berlenga Island. No significant differences were observed between bird species. These findings highlights the need for further investigation into Borrelia- soft tick- seabird interactions, and the potential infection risks associated with gull breeding habitats, particularly in areas of human-wildlife contact.