Effects of Rice Field Phenology on Breeding Parameters of Heron Colonies in the East of the Iberian Peninsula

Effects of Rice Field Water Cycles on the Breeding Biology of Grey Heron (Ardea cinerea) and Conservation Implications

“…L'Albufera de Vàlencia covers an area of 21,120 ha, of which 2,800 ha correspond to a shallow lagoon and 290 ha of marshland vegetation, which is fed by crop returns and water from the fluvial systems of the Júcar and Turia rivers. The rice fields cover 14,000 ha and represent an important habitat for the waterfowl community, both resident and migratory, especially during the breeding season, as they are the main feeding area for the latter (Fasola and Ruiz 1996, Fasola et al 1996, Dies and Dies 1998, Prosper 2000, Toral and Figuerola 2010, Antón-Tello et al 2021, Forti et al 2021b). The hydrological dynamics of the paddy fields depend on the amount of water that enters the system twice a year.…”

“…However, there are numerous species of aquatic birds that also nest in the area, including species with some conservation category. These species, which also feed in the rice field during their reproductive season, could also be affected by rice field management, as has been observed in other heron species in the area (Forti et al 2021b). Therefore, the success of the breeding populations in L'Albufera de València requires planning and management of the protected area that considers the biological and reproductive requirements of the species.…”

“…However, in recent decades, rice field management has varied in terms of the start and duration of flooding periods during the annual period and in agronomic practices during the growing season, with flooding starting later and for shorter periods, among others. These changes have affected negatively both the quality of the feeding habitat for herons and other birds, as well as the reproductive success of some species such as the Little Egret ( Egretta garzetta ) or Cattle Egret ( Bulbucus ibis ) (Antón-Tello et al 2021, Forti et al 2021b). According to these studies, it is to be expected that the reproductive biology of the Grey Heron in L'Abufera de Vàlencia could have been affected, both in phenology and reproductive success, due to the effect of new practices in rice cultivation, which could also be related to the population declines that have been reported for the area (Generalitat Valenciana 2021, Forti et al 2021a).…”

“…Similarly, the presence and extent of rice paddies has been related to population trends, colony size and reproductive success (Hafner et al 1987, Tourenq et al 2000, Fasola and Brangi 2010, Fujioka et al 2010, Ramo et al 2013, Forti et al 2021a, Fasola et al 2022). However, these aspects of waterbird biology are associated with the rice cultivation practices and rice flooding regime (Ibañez et al 2010, Cardarelli et al 2017, Forti et al 2021b. Substitution of rice fields by another crops or the change to practices where the months of flooding or the depth of the water sheet are reduced, may have negative effects on the populations of some species and their reproduction (Toral et al 2012, Cardarelli et al 2017, Fasola et al 2022).…”

Editorial: On Authorships, Ethics, and Inclusion

“…Forti et al . (2022) add an important investigation to literature underscoring the importance of rice field conditions to the breeding of Grey Herons Ardea cinerea in Spain. Herons favoured semi-flooded fields over sown fields suggesting careful management of rice fields to tie in with breeding requirements of waterbirds can be critical in areas where rice fields are common.…”