Avian malaria,haematocrit,and body condition in invasive wetland passerines settled in southwestern Spain

Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds.Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native passerines,with exotic species underrepresented.However,introduced species may carry on and spread new pathogens to native species,and play a role on parasite transmission cycle in invaded bird communities as pathogen reservoir.Here,we molecularly assess the prevalence and diversity of haemosporidian parasites in three introduced wetland passerines(the Red Avadavat Amandava amandava,the Yellow-crowned Bishop Euplectes afer,and the Common Waxbill Estrilda astrild)captured during the same season in southwestern Spain.We also explored the relation between parasite infection,body condition,haematocrit,and uropygial gland volume.We detected an overall parasite prevalence of 3.55%,where Common Waxbills showed higher prevalence(6.94%)than Red Avadavats(1.51%).None Yellow-crowned Bishops were infected with haemosporidians.Almost 60%of infections were caused by Leucocytozoon,and about 40%by Plasmodium.We identified four unique lineages of Plasmodium and three of Leucocytozoon.Moreover,91%of the identified host-parasite interactions represented new host records for these haemosporidian parasites.Parasite infection was not related to body condition,haematocrit,and uropygial gland volume of the wetland passerines.Haematocrit values varied seasonally among bird species.Additionally,haematocrit was positively related to body condition in the Yellow-crowned Bishops,but not in the other species.Red Avadavats had higher haematocrit levels than Yellow-crowned Bishops,whereas Common Waxbills showed the lower haematocrit values.The uropygial gland volume was positively correlated with body condition in all bird species.Common Waxbills showed higher uropygial gland volumes related to their body size than birds from other two species.These outcomes highlight the importance of exotic invasive species in the transmission dynamics of haemosporidian parasites.

Simultaneous analysis of the intestinal parasites and diet through eDNA metabarcoding

Agricultural expansion and intensification are having a huge impact on plant and arthropod diversity and abun-dance,affecting food availability for farmland birds.Difficult food access,in turn,can lead to immunosuppression and a higher incidence of parasites.In the studies designed to examine changes in the diet of birds and their par-asites,metabarcoding is proving particularly useful.This technique requires mini-barcodes capable of amplifying the DNA of target organisms from fecal environmental DNA.To help to understand the impact of agricultural expansion on biodiversity,this study sought to design and identify mini-barcodes that might simultaneously as-sess diet and intestinal parasites from the feces of farmland birds.The capacity to identify diet and parasites of 2 existing and 3 newly developed mini-barcodes was tested“in silico”in relation to the behavior of a reference eukaryotic barcode.Among the newly designed mini-barcodes,MiniB18S_81 showed the higher taxonomic cover-age of eukaryotic taxa and a greater amplification and identification capacity for diet and parasite taxa.Moreover,when it was tested on fecal samples from 5 different steppe bird species,MiniB18S_81 showed high taxonomic resolution of the most relevant diet and parasite phyla,Arthropoda,Nematoda,Platyhelminthes,and Apicomplexa at the order level.Thus,the mini-barcode developed emerges as an excellent tool to simultaneously provide detailed information regarding the diet and parasites of birds,essential for conservation and management.

Do non-target species visit feeders and water troughs targeting small game?A study from farmland Spain using camera-trapping

Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife,but factors affecting the use of food and water by non-target species are poorly known.We evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of Spain.Feeders and water troughs were either“protected”(when surrounded by more than 50%of shrubs/forest)or“open”(in the opposite case).A total of 18948 photos from 5344 camera-trapping days depicted animals,and 75 species were identified.Feeders and water troughs were visited by target species(partridges and lagomorphs,55.3%of visits)and non-target species(44.7%of visits).Among the latter,corvids were themost common(46.1%of visits),followed by rodents(26.8%),other birds(23.6%,mainly passerines),columbids(1.9%),and other species at minor percentages.The highest proportion of visiting days to feeders and water troughs was from corvids(0.173)followed by otherbirds(0.109)and rodents(0.083);the lowest proportion was recorded for columbids(0.016).Use intensity and visit frequency of water troughs tripled that recorded in feeders,and visits to open feeders/troughs were approximately twice those to protected ones.In summary:feeders and water troughs targeting small game species are also used regularly by non-target ones;they should be set close to cover to optimize their use by non-target species that are not competitors of target species(though corvids may visit them);water availability should be prioritized where drought periods are expected.