Data from: Nest survival in year-round breeding tropical Red-capped Larks (Calandrella cinerea) increases with higher nest abundance but decreases with higher invertebrate availability and rainfall

Nest survival is critical to breeding in birds and plays an important role in life-history evolution and population dynamics. Studies evaluating the proximate factors involved in explaining nest survival and the resulting temporal patterns are biased in favor of temperate regions. Yet, such studies are especially pertinent to the tropics, where nest predation rates are typically high and environmental conditions often allow for year-round breeding. To tease apart the effects of calendar month and year, population-level breeding activity and environmental conditions, we studied nest survival over a 64-month period in equatorial, year-round breeding red-capped larks Calandrella cinerea in Kenya. We show that daily nest survival rates varied with time, but not in a predictable seasonal fashion among months or consistently among years. We found negative influences of flying invertebrate biomass and rain on nest survival and higher survival of nests when nests were more abundant, which suggests that nest predation resulted from incidental predation. Although an increase in nest predation is often attributed to an increase in nest predators, we suggest that in our study, it may be caused by altered predator activity resulting from increased activity of the primary prey, invertebrates, rather than activity of the red-capped larks. Our results emphasize the need to conduct more studies in Afro-tropical regions because proximate mechanisms explaining nest predation can be different in the unpredictable and highly variable environments of the tropics compared with the relatively predictable seasonal changes found in temperate regions. Such studies will aid in better understanding of the environmental influences on life-history variation and population dynamics in birds.,Nest survival in year-round breeding tropical Red-capped LarksYear round nest monitoring data on Red-capped Larks collected in the field between the period 2011-2016. Also included are: (1) weather data on rain, maximum and minimum temperature collected with a local weather station located at the field site, (20 invertebrates biomass data sampled monthly as a proxy for food availability and (3) nest index quantifying number of new nests found in a month per 10 person hours of search effort as a measure on nest abundanceNest success Red_capped lark.xlsx

Data from: No down-regulation of immune function during breeding in two year-round breeding bird species in an equatorial East African environment

Some equatorial environments exhibit substantial within-location variation in environmental conditions throughout the year and yet have year-round breeding birds. This implies that breeding in such systems are potentially unrelated to the variable environmental conditions. By breeding not being influenced by environmental conditions, we become sure that any differences in immune function between breeding and non-breeding birds do not result from environmental variation, therefore allowing for exclusion of the confounding effect of variation in environmental conditions. This create a unique opportunity to test if immune function is down-regulated during reproduction compared to non-breeding periods. We compared the immune functions of sympatric male and female chick-feeding and non-breeding Red-capped Calandrella cinerea and Rufous-naped Larks Mirafra africana in equatorial East Africa. These closely-related species occupy different niches and have different breeding strategies in the same grassland habitat. Red-capped Larks prefer areas with short grass or almost bare ground, and breed during low rainfall periods. Rufous-naped Larks prefer areas of tall grass and scattered shrubs and breed during high rainfall. We measured the following immune indices: nitric oxide, haptoglobin, agglutination and lysis, and measured total monthly rain, monthly average minimum (Tmin) and maximum (Tmax) temperatures. Contrary to our predictions, we found no down-regulation of immune function during breeding; breeding birds had higher nitric oxide than non-breeding ones in both species, while the other three immune indices did not differ between breeding phases. Red-capped Larks had higher nitric oxide concentrations than Rufous-naped Larks, which in turn had higher haptoglobin levels than Red-capped Larks. Tmax was higher during breeding than during non-breeding for Red-capped Larks only, suggesting potential confounding effect of Tmax on the comparison of immune function between breeding and non-breeding birds for this species. Overall, we conclude that in the two year-round breeding equatorial larks, immune function is not down-regulated during breeding.,Nox data NK RCL RNLThis is data for the immune index nitric oxide (mmol/ml) for two sympatric species - Red-capped Lark, Calandrela cinerea and Rufous-naped Lark, Mirafra africana - in North Kinangop, Kenyahp data NK RCL RNLThis is data for the immune index haptoglobin (mg/ml) for two sympatric species - Red-capped Lark and Rufous-naped Lark - in North Kinangop, KenyaHLHA data NK RCL RNLThis is data for the immune indices lysis and agglutination (titre) for two sympatric species - Red-capped Lark and Rufous-naped Lark - in North Kinangop, KenyaMass data NK RCL RNLThis is data for mass (g) for two sympatric species - Red-capped Lark and Rufous-naped Lark - and environmental conditions (rain (mm), average minimum and average maximum temperatures 0C) in their environment in North Kinangop, Kenya

Additional file 3 of Cloacal microbiota are biogeographically structured in larks from desert, tropical and temperate areas

Additional file 3