DOI: 10.5061/dryad.9rt5dd8
title: Data from: No down-regulation of immune function during breeding in two year-round breeding bird species in an equatorial East African environment

description: 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.
description: 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