Why do cervids feed on aquatic vegetation?
Consumption of aquatic plants is rare among cervids, despite the common occurrence of this form of vegetation. However, the paucity of literature reporting on this feeding behaviour suggests that Na (but also other minerals), protein, and the ubiquitous availability of aquatic vegetation may play a role in its consumption. We present results quantifying those factors that regulate the consumption of aquatic plants in the Iberian red deer. We focussed our study primarily on two questions: (i) what nutritional values are red deer seeking in the aquatic plants?; and (ii) why do red deer primarily use aquatic plants during the summer? A comparison of the seasonal variations in Na content between terrestrial vs. aquatic vegetation did not fully support the hypothesis that aquatic plants are being consumed more in summer because of any seasonal variation in Na availability. The Na content in the aquatic vegetation was adequate all the year-round; whereas, the Na content in the terrestrial vegetation was consistently deficient. However, a greater summer content of essential minerals and protein in the aquatic vegetation may be the cause for their consumption exclusively during the summer. We suggest that seasonal variations in the consumption of aquatic vegetation by cervids is primarily driven by temporal variations in the nutrient content, combined with seasonal variations in the physiological demands for these nutrients.
Department of Animal Science and Food Processing, Faculty of Tropical AgriSciences, Czech University of Life Sciences, Kamýcka 129, 165 21 Prague 6, Suchdol, Czech Republic. Electronic address: francisco.ceacero@outlook.com.
Francisco
F
Ceacero
Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain; Animal Science Tech. Applied to Wildlife Management Res. Group, IREC Sec. Albacete (UCLM-CSIC-JCCM), 02071 Albacete, Spain; Sección de Recursos Cinegéticos y Ganaderos, Instituto de Desarrollo Regional (IDR), Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain. Electronic address: tomas.landete@uclm.es.
Tomás
T
Landete-Castillejos
Centre for African Ecology, School of Animal, Plant & Environmental Sciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa. Electronic address: maria.mirandaroves@gmail.com.
María
M
Miranda
Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain; Animal Science Tech. Applied to Wildlife Management Res. Group, IREC Sec. Albacete (UCLM-CSIC-JCCM), 02071 Albacete, Spain; Sección de Recursos Cinegéticos y Ganaderos, Instituto de Desarrollo Regional (IDR), Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain. Electronic address: andresjose.garcia@uclm.es.
Andrés J
AJ
García
Laboratorio de Ciencia e Ingeniería de Materiales (CIMA), Instituto de Desarrollo Regional (IDR), Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain. Electronic address: alberto.martinez@uclm.es.
Alberto
A
Martínez
Departamento de Ciencia y Tecnología Agroforestal y Genética, Universidad de Castilla-La Mancha (UCLM), 02071 Albacete, Spain; Animal Science Tech. Applied to Wildlife Management Res. Group, IREC Sec. Albacete (UCLM-CSIC-JCCM), 02071 Albacete, Spain. Electronic address: laureano.gallego@uclm.es.
Laureano
L
Gallego
D000818:Animals; D059001:Aquatic Organisms / Q000737:chemistry; D003670:Deer / Q000502:physiology*; D004032:Diet; D005247:Feeding Behavior / Q000502:physiology*; D008903:Minerals / Q000032:analysis; D009753:Nutritive Value; D014674:Plant Proteins, Dietary / Q000032:analysis; D010944:Plants / Q000737:chemistry; D061005:Ponds; D012621:Seasons; D012964:Sodium / Q000032:analysis
D008903:Minerals; D014674:Plant Proteins, Dietary; D012964:Sodium
Aquatic vegetation; Diet seasonality; Minerals; Protein; Red deer; Sodium