Breeding phenology of Common Redstart (Phoenicurus phoenicurus) and its reproduction biology with artificial nests in Northeastern Ukraine

The paper describes investigations on the reproduction biology (nesting, clutching, hatching, fledglings` departure) of the Common Redstart (Phoenicurus phoenicurus) in artificial nest boxes (AN) in Northeastern Ukraine. There were three sites of research: Hetman NNP, NPP “Gomilshansky Forests”, and RLP “Feldman Ecopark”. The research was performed during the nesting period from the first week of April to the first week of July in 2015‒2020. Annually, 5‒8 bird counts were conducted at each site. The first complete egg clutches at Hetman NNP were observed from 08.05 to 17.05 (2015‒2020) and at NPP “Gomilshansky Forests” from 02.05 to28.05 (2017‒2020). Dates of the first egg laying, at various conditions, had inter-annual variability because of unstable weather conditions in May. The average parameters of nests in AN at Hetman NNP were the following: diameter of nests (D) ‒ 124.1±6.3 mm; diameter of trays (d) ‒ 61.5±1.7 mm; nest height (H) ‒ 63.5±9.4 mm; depth of trays (h) ‒ 48.6±2.7 mm; nest mass (m) ‒ 43.7±3.8 mm. The size of complete clutches in Northeastern Ukraine was calculated when eggs were incubated. According to the average indicators, during 2015‒2020, the average size of the clutch was 6.9±0.3 (5‒8) eggs at Hetman NNP, 6.2±0.4 (6‒8) eggs at NPP “Gomilshansky Forests” and 8.5±0.5 (8‒9) eggs at RLP “Feldman Ecopark”. Incubation period of Ph. phoenicurus lasted on average for 15‒20 days.

Nest Characteristics of the Sumatran Orangutan (Pongo abelii) in the Wildlife Sanctuary Soraya Station in Aceh Province, Indonesia

Orangutans (Pongo spp.) populations used to be widely distributed throughout Southeast Asia, from Java in the south to the Southern China in the north during the Pleistocene. Their populations have declined up to 75% of their original size and are now distributed only in parts of the tropical rainforests of Borneo and Sumatra. Pongo pygmaeus, Pongo tapanuliensis and Pongo abelii are the three most representative species, in this study, here we discussed the latter. Sumatran forests are generally suffering from deforestation with rates ranging from 3.74% to 49.85% between 2000 and 2012. Thus, human wildlife conflict intensity has escalated and gained more traction. Orangutans are known as arboreal great apes and need to build nests for resting. We applied the transect line method (three transects; each 1,000 m long) at different elevations in Soraya Research Station, Gelombang Village, Sultan Daulat sub-district, Subulussalam district, and assessed the nest characteristics. The characteristics are: (1) nesting position referring to the position of nest on a tree; (2) nest successional stages defining the age and leaf decay used in constructing a nest indicated with I (new) until V (almost gone); and (3) nest density to predict the density of nest per square km. Afterwards, the identified nesting trees along the transect were further identified based on their species, and assessed based on three characteristics (the tree height, diameter and the height of a nest measured from the soil). A total of 27 nests were found, and 44% were located in transect III or at the riparian. Out of 27, four orangutans’ nests were found on Moraceae (Streblus elongatus) and Myrtaceae (Syzigium spp.), while three nests were found on Dipterocarpus sp. The tree height, tree diameter and nest height were 10 m–25 m (mean = 17.5 m; SD = ± 0.25), 10 cm–30 cm (mean = 20 cm; SD = ± 0.4) and 16 m–20 m (mean = 18 m; SD = ± 0.35), respectively. Meanwhile, nest density calculated based on the form: d = [N/ (L* 2w)], and the values obtained were 8.4, 13.45, 26.9 nests/km2 located on transect I, II and III or at the riparian. The most commonly found nest successional stages and position were stage III and position 3, respectively. This study could serve as a baseline research in primate conservation and nest characterisation could be used as guidance for any future activity planning (e.g. tree reforestation) in a particular region and the existence of various tree species diversity are indispensable for maintaining orangutan habitats’ quality.

Coevolution between Himalayan cuckoos and two sympatric Pycnonotidae hosts

Selection due to cuckoo parasitism is responsible for the evolution of anti-parasitism defenses in hosts. Different host species breeding sympatrically with a single parasitic cuckoo may evolve different strategies to reduce the risk or counter cuckoo parasitism, resulting in different interactions between cuckoos and hosts in areas of sympatry. Here, we studied the coevolutionary interactions between Himalayan cuckoos Cuculus saturatus and two sympatric and closely related potential hosts belonging to the family Pycnonotidae, the brown-breasted bulbul Cuculus saturatus and the collared finchbill Spizixos semitorques. We investigated parasitism rates and nest site selection (nest height, nest cover, human disturbance, perch height, forest distance, and degree of concealment) related to parasitism risk, nest defense against a cuckoo dummy, and egg rejection against cuckoo model eggs. Bulbuls used specific nest sites that were further away from forests than those of finchbills, and they behaved more aggressively toward cuckoos than finchbills. In contrast, bulbuls possessed moderate egg rejection ability, while the finchbill rejected 100% of cuckoo model eggs. We suggest that selection of a nest site away from forests by the bulbul explains the absence of parasitism by Himalayan cuckoos. We suggest that these interspecific differences in nest site selection and nest defense indicate alternative responses to selection due to cuckoos.

Breeding Performances of the European Blackbird (Turdus merula) in Morocco: Habitat Selection, Breeding Phenology, and Breeding Success

The European Blackbird (Turdus merula) is a widespread species. In Morocco, available knowledge on this species is limited to a few descriptive pieces of information with no detailed data provided. With climate change and the intensification of agricultural activities, the study of the breeding performances of this species is indispensable for management purposes. This study investigates breeding biology, nesting habitats, breeding chronology, and reproductive success of the European Blackbird in both apple orchards and surrounding woody vegetation at Ait Ayach (Morocco) between March and August 2016. We monitored weekly nest status, nesting sites, breeding dates, and failure factors. Results showed that the European Blackbird nests mainly in apple orchards, on Golden Delicious and Starkrimson Delicious trees. Nest height above the ground was 214.15 ± 0.09 cm. Blackbird nests were cup-shaped with medium size dimensions and built from twigs, including dry leaves, stems, and roots walled by the mud. Breeding activities started firstly by nest construction during the last week of April, secondly by egg laying during the first week of May, and thirdly by hatching during the second week of May. Among the 74 surveyed nests, 100% were active during the nesting phase and 88.38% of eggs have succeeded during the incubation phase. In total, 69.03% of chicks have been emancipated. In short, 15.9% of clutches were attacked by predators, 14.35% of clutches were failed due to nest desertion, and 8.75% of chicks were dead. Our study provides the first and only detailed data on reproductive parameters of the European Blackbird in Moroccan ecosystems. Data collected from this study provide valuable information for long-term monitoring of the Moroccan Blackbird population. Additionally, our data offer a possibility of large-scale comparative studies of the reproductive ecology of the Blackbird species.

Can chemical cues from a predator change the nest-selection of birds?

The nest-selection process of many birds can be affected by traces of potential predators. However, it remains debatable if birds are capable of recognizing and responding to chemical cues of predators when selecting their nest sites. To investigate this, I installed a pair of nest boxes at 12 sites in 2013 and 2014 and 24 sites in 2015 and 2016, each with nest conditions that differed for two variables, that is, height (high or low), hole depth (deep or shallow). Under these experimental conditions, tree swallows displayed a strong preference for high nests over low ones and deep hole nests over shallow holes. In a consecutive experiment, we applied chemical cues (i.e. urine, feces) of domestic cats to the preferred nests to determine if this would alter the nests selected; the chemical cues led to a stepwise alteration in the nests selected. The birds changed their nest selection by chemical cues of a predator when one variable (nest height or hole depth) was applied. Interestingly, however, when provided with a choice between the most preferred nest combination (high and with a deep hole) and the least preferred nest combination (low and with a shallow hole), tree swallows selected the most preferred nest even in the presence of the chemical cues.

A Preliminary Study on the Small Population Paradigm and Nesting Biology of Rose-Ringed Parakeets (Psittacula Krameri) in Gujar Khan, Pakistan

Rose-ringed parakeet (P. krameri) is commonly found native psittacid in Pakistan. It is most popular companion bird in Pakistan. It is an unprotected species as per The Punjab Wildlife Act, 1974. The objectives of the present study were to study its population paradigm and basic nesting biology in the Gujar Khan, Punjab, Pakistan. Previously, no studies were carried out to assess its live and vacant nest cavities, nesting site, nest height, cavity position on substrate, and potential roosts in the area. Moreover, this study also assesses the potential threats and factors in this area and conservation of the parakeet. Results show that in the study area (36.77%) active and (63.22%) inactive nests were found. A total of 10 tree species were utilized to make nests. It was found Ficus bengalensis, Syzygium cumini, Morus alba, Melia azedarach and Broussonetia papyrifera as the most used tree species for nesting due to more frequencies and old ages. Parakeets make nest at 3-11 m height. The preferred nest height (42.48%) was in the range of 7-9 m, while (5.88%) least at 3-5 m height. For safety reasons they made more nests (45.09%) on the tree trunk followed by terminal (31.37%) and at fork (23.52%). Due to smaller thriving population we found only (mean=7±4) parakeets during roost counting. Severe cutting of trees, destruction of its habitat and poaching for selling in the bird market are the main causes of its population decline. Government must change its status from unprotected to protected species and should ban its dealing for pet.

The effects of forest edge and nest height on nest predation in a U.K. deciduous forest fragment

It has been previously hypothesised that nest predation is higher at forest edges. This has important conservation implications for the increasingly fragmented U.K. climax community. I aimed to test the generality of this edge effect in a mixed deciduous forest fragment which borders open grassland. Artificial nests containing a combination of quail and plasticine eggs were used, at ground and arboreal levels. I found an overall edge effect on nest predation rates, however this effect was not specifically seen in ground nests. Ground nests experienced significantly higher levels of predation than arboreal nests. I suggest this edge effect is due in part to the steep productivity gradient over the ecotone.

Adaptation and constraint shape the evolution of growth patterns in passerine birds across the globe

Background Growth trajectories should be adapted to selective factors of each species’ environment. However, major shaping forces of growth and development are unclear, especially when studying several traits at once. Birds provide an ideal opportunity to analyze growth patterns across species due to there being enough available data. We tested the relative importance of nest predation risk, the number of care-givers, nest height, foraging substrate, clutch size, and latitude on growth patterns of passerine birds (Passeriformes) using phylogenetic comparative methods. Specifically, we studied the evolution of fledging time, average and peak growth rates, and relative development at fledging of body mass and tarsus, wing, and tail length. Results Using a comprehensive literature search and data quality control, we obtained data on growth in 231 species based on 295 populations. Species with long development in the nest grew slowly and had well-developed traits at fledging. Species breeding under high nest predation risk, building their nests close to the ground, and those living in northern temperate regions fledged early and grew fast, sometimes fledging with less developed body mass and traits critical for locomotion (tarsus, wing, and tail). On the other hand, the number of caring adults, clutch size, and species’ foraging substrate had very limited predictive value for growth patterns across passerine species. Conclusions Shortening of the nestling period was a primary means of accelerating development (in relation to nest predation, nest height, and latitude), sometimes supplemented by higher peak growth rates of body mass, tarsus, and wing (especially in relation to latitude). Overall growth patterns of passerines were adaptively tuned to nest predation risk and nest height, with northern temperate species having especially short nestling periods and fast growth rates of body mass, tarsus, and wing.