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Understanding the population dynamics of endangered species is crucial to their conservation. Stochastic population models can be used to explore factors involved in population change, contributing to the understanding of a species’ population dynamics. Norfolk Island Green Parrots Cyanoramphus cookii have undergone significant population fluctuations in the last 50 years. Since 2013, most nestlings hatched in managed, predator-proofed nest sites have been individually marked. These nests have been considered the primary source of population growth. Yet, in 2021, most adult birds were unmarked, raising the question of whether unmarked parrots have been entering the population through undetected breeding in natural nests, and to what extent. We modelled Green Parrot population growth between 2013 and 2021 using stochastic population models in VORTEX to explore the potential dynamics involved in the observed population growth. Basic models involving breeding only in managed nests produced population estimates between 158 and 266, whereas more complex models that included breeding in unmanaged nests, and accounted for the large proportion of unmarked birds, produced population estimates between 360 and 1,041. We conclude that natural nests may have played a significant role in the population growth since 2013. If this is the case, broad-scale predator control may be largely responsible. Furthermore, our study shows how population models may be used to infer underlying demographic processes and inform conservation strategies, even in instances of data scarcity. Our method can be applied to other threatened species, and may prove particularly useful for small populations whose population dynamics remain unclear.

Translocations are one of the most important conservation actions in the recovery of endangered species, these imply the movement of live individuals from one area to another. To ensure the success of translocations, different logistics and species-specific ecological factors need to be considered. Since the early 2000’s, there have been calls to reintroduce the endangered cooperative breeding Floreana mockingbird, to Floreana Island (Galápagos Archipelago) where they became locally extinct due to habitat loss and invasive species. The species currently inhabiting two small islets off the coast of Floreana with no recent history of connection between populations. However, our understanding of reintroduction strategies for the mockingbird is based on monogamous breeding species, not on cooperative breeding species. In this thesis, I explored demographic and behavioural aspects of the species that might facilitate the reintroduction to Floreana. Firstly, I described a non-invasive method that will help will the correct sexing identification and monitoring of Floreana mockingbirds. Furthermore, I assessed the probability of survival of the species using capture-mark-recapture (CMR) models and the influence of precipitation on the survival rate, recruitment of individuals, and population growth. Overall, the population seem to be stable with a slight decrease in one of the populations. Additionally, I explored ecological factors such as vocalization and sociality. I investigated the hypothesis of possible differences in vocalisations between individuals from the two remnant populations. I found an acoustic divergence between populations that could be explained by the influence of cultural drift and morphological differentiation as an effect of isolation, lack of gene flow, and cultural exchange. Finally, I investigated the social structure of the Floreana mockingbird and the probability of group disruption during translocations. I found that mockingbirds live in a highl

Background: Haemoproteus and Plasmodium species are widespread avian blood parasites. Several Plasmodium species are known for their high virulence and have caused significant declines in naïve bird populations. The impact of closely related Haemoproteus parasites is largely unknown. Recently we reported a lethal disease in two parrot aviaries caused by Haemoproteus parasites. Results: Here we show that the causative pathogen Haemoproteus minutus is responsible for further 17 lethal outbreaks in parrot aviaries in Denmark, Germany and Great Britain. All affected parrots are endemic to Australasia and South America. We sequenced the cytochrome b gene from megalomeront-infected muscle tissue of 21 parrots and identified the two lineages TUPHI01 and TURDUS2 as causative agents, commonly naturally infecting the common blackbird (Turdus merula) and the song thrush (Turdus philomelos), respectively, in the Palaearctic. No intraerythrocytic parasite stages were found in any of the parrots. We failed to detect H. minutus in invasive Indian ring-necked parakeets (Psittacula krameri) in Germany. Together this suggests that abortive infections with two virulent lineages of H. minutus are lethal for naïve parrot species from Australasia and South America. We asked whether we could detect H. minutus in New Zealand, where its Turdus hosts were introduced in the 1800s. We therefore tested invasive blackbirds and song thrushes, and the co-existing endemic red-fronted parakeet (Cyanoramphus novaezelandiae) population on three New Zealand islands. No Haemoproteus spp. DNA was detected in all blood samples, indicating absence of transmission. Conclusions: The results of this study show that captive parrots in Europe are threatened by two lineages of an otherwise benign parasite of Turdus spp. Aviary collections of parrots should be protected from Culicoides spp. vectors in Europe. Animal trade and climate changes extending the current vector and parasite distribution have to be consid, Ministerio de Economía y Competitividad (MINECO), Swiss National Science Foundation (SNSF), New Zealand Department of Conservation, Massey University, Motuihe Island Trust, Tawharanui Open Sanctuary Supporters Inc., Auckland Regional Council, National Council of Science Mexico (CONACYT), Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

[Background] Parasites can exert selection pressure on their hosts through effects on survival, on reproductive success, on sexually selected ornament, with important ecological and evolutionary consequences, such as changes in population viability. Consequently, hemoparasites have become the focus of recent avian studies. Infection varies significantly among taxa. Various factors might explain the differences in infection among taxa, including habitat, climate, host density, the presence of vectors, life history and immune defence. Feeding behaviour can also be relevant both through increased exposure to vectors and consumption of secondary metabolites with preventative or therapeutic effects that can reduce parasite load. However, the latter has been little investigated. Psittaciformes (parrots and cockatoos) are a good model to investigate these topics, as they are known to use biological control against ectoparasites and to feed on toxic food. We investigated the presence of avian malaria parasites (Plasmodium), intracellular haemosporidians (Haemoproteus, Leucocytozoon), unicellular flagellate protozoans (Trypanosoma) and microfilariae in 19 Psittaciformes species from a range of habitats in the Indo-Malayan, Australasian and Neotropical regions. We gathered additional data on hemoparasites in wild Psittaciformes from the literature. We considered factors that may control the presence of hemoparasites in the Psittaciformes, compiling information on diet, habitat, and climate. Furthermore, we investigated the role of diet in providing antiparasitic secondary metabolites that could be used as self-medication to reduce parasite load., [Results] We found hemoparasites in only two of 19 species sampled. Among them, all species that consume at least one food item known for its secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, were free from hemoparasites. In contrast, the infected parrots do not consume food items with antimalarial or even general antiparasitic properties. We found that the two infected species in this study consumed omnivorous diets. When we combined our data with data from studies previously investigating blood parasites in wild parrots, the positive relationship between omnivorous diets and hemoparasite infestation was confirmed. Individuals from open habitats were less infected than those from forests., [Conclusions] The consumption of food items known for their secondary metabolites with antimalarial, trypanocidal or general antiparasitic properties, as well as the higher proportion of infected species among omnivorous parrots, could explain the low prevalence of hemoparasites reported in many vertebrates.

In this study, a visit to the remote Kermadec archipelago and the translocation of two parakeet species to novel sites opened up opportunities to document aspects of the biology of free-living and captive-bred parakeets. Four years after the eradication of cats and rats on Raoul Island by the Department of Conservation, the Kermadec redfronted parakeet has naturally recolonised this site, potentially from the adjacent Herald Islets. Over a period of three weeks in March-April 2008, 100 parakeets were captured on Raoul Island and the first evidence of nesting of the species at this site since 1836 was recorded. These observations reinforce the view that eradication of introduced predators such as cats and rats is a requisite for the recovery and establishment of populations of New Zealand parakeets. These observations also suggest that strategic eradication of cats and rats can facilitate the natural dispersal of parakeets. Taking into account the remarkable recolonisation of parakeets on Raoul Island and the existence of islands free of introduced mammalian predators and red-fronted parakeets in the Hauraki Gulf, a translocation of parakeets was envisaged. Between April and May 2008, 32 red-fronted parakeets were translocated from Little Barrier Island to Motuihe Island, in the first translocation of the species within the Hauraki Gulf in 32 years. Alongside such transfer, a total of 62 captive-bred Malherbe’s parakeets were monitored on Maud Island, in the Marlborough Sounds. Because the translocations of red-fronted and Malherbe’s parakeets were temporally close, a unique opportunity to study translocated free-living and captive-bred parakeets was identified. The focus of monitoring on both sites was the detection of successful nesting attempts, a short-term measure of translocation success. On both sites (Motuihe and Maud Islands) evidence of successful nesting was found within a year of the release of the first flocks. As part of the planning steps for the trans

Screening for pathogenic micro-organisms is an essential component of translocation-based conservation management. While there are some data on pathogens in New Zealand passerines, little is known about the distribution and prevalence of pathogens infecting New Zealand Psittaciformes. We conducted a survey for pathogens of the vulnerable New Zealand endemic red-crowned parakeet Cyanoramphus novaezelandiae in two wild populations (Little Barrier Island and Raoul Island), and in a translocated population (Tiritiri Matangi Island). A total of 101 cloacal samples were tested for Salmonella and Yersinia. Of these, 82 samples were also tested for Campylobacter. None of these microorganisms were detected. Although our sampling effort was insufficient to detect a low prevalence of Campylobacter, modelling of minimum detectable prevalence of Salmonella and Yersinia indicates that these micro-organisms would have been detected if present as common or chronic conditions of red-crowned parakeets at these sites.

The reproductive ecology of a translocated population of red-crowned kakariki (Cyanoramphus novaezelandiae) was monitored during 2004-2006, covering two breeding seasons on Tiritiri Matangi Island. Red-crowned kakariki nested in tree cavities, ground burrows and in vegetation clusters located in forest remnants, grasslands and replanted vegetation as well as in nestboxes. There was a marked difference in reproductive success between the two breeding seasons. In 2004-2005 1.4 fledglings per breeding pair were produced. In contrast. 3.4 fledglings per breeding pair were produced in 2005-2006. This increase was the result of changes in loss rate during the nesting cycle. Nest failure occurred in 57% of nests in 2004-2005 whereas only 8% of nests were affected in 2005-2006. In both breeding seasons, incubation was the main stage of losses. Clutches hatched with various degrees of asynchrony. Brood sizes ranged from one to nine nestlings. Within broods, nestlings of different hatching ranks reached similar mass at fledgling. Likewise, nestlings of different hatching ranks gained similar weight over the linear portion of the growth curve and grew wings at a similar rate. However, last hatched nestlings fledged with shorter wings. Furthermore, mortality was higher for last hatched nestlings. Sex ratios at the clutch level and at fledgling did not deviate from parity. However, at the clutch level there was a higher proportion of males in clutches laid early and middle in the breeding season. Various lines of evidence suggest that food availability has a direct effect on reproductive success of red-crowned kakariki and can exacerbate the costs of asynchronous hatching. Therefore it is a priority to investigate natural changes in food resources of the red-crowned kakariki and to assess the potential of direct management to improve the conservation of the species.

Tigridia pugana (Iridaceae: Tigridieae) is described as a new species. It is characterized by producing bulbils in the axils of the cauline leaves. The flower of Tigridia pugana resembles that of T. pulchella B.l. rob. but differs by having longer style branches that are bifid their full length, longer inner tepals and shorter ovary and fruit. So far, the new species is known only from the sierra de la campana and sierra de manantlán, in the state of Jalisco, mexico., se describe Tigridia pugana. la nueva especie se caracteriza por producir bulbilos en las axilas de las hojas caulinares. La flor de T. pugana es similar a la de T. pulchella B.l. Rob. pero se diferencian de esta última por tener ramas del estilo más largas y bífidas en toda su longitud, tépalos internos más largos y ovario y fruto más pequeños. Hasta ahora, T. pugana sólo se conoce de las sierras de la campana y manantlán, en el estado de Jalisco, méxico.

Based on cytological, palynological, and DNA evidence, we propose the elevation of Nemastylis subgenus Colima to the generic status to include Nemastylis convoluta. The new genus is characterized by its united filaments, free anthers with longitudinal dehiscence, style divided into three branches with six arms at right angles, apical stigmatic surface, absence of nectaries, lack of mucro between the style arms and bisulcate pollen grains. A preliminary study based on morphological variation and DNA sequences variation suggests a close phyllogenetic relationship between Colima and the genera included within the subtribe Tigridiinae. However the relationships of Colima at the generic level are not fully resolved by the molecular analysis. Finally, we describe and illustrate a new species of Colima from El Tuito, Jalisco. This new species is characterized by its winged stems, pedicels, ovaries and fruits. In addition, the tepals are creamy yellow, oblanceolate with acuminate apex and a smaller androgynoecial apparatus than that of Colima convoluta., Con base en información citológica, palinológica y secuencias de ADN se propone la elevación de Nemastylis subgénero Colima al nivel de género para incluir en éste a Nemastylis convoluta. Este nuevo género se caracteriza por presentar filamentos unidos, anteras libres con dehiscencia longitudinal, estilo dividido en tres brazos con seis ramas dispuestas en ángulo recto, superficie estigmática apical, falta de nectarios, ausencia de mucrón entre las ramas del estilo y polen bisulcado. Un estudio preliminar basado en la variación de caracteres morfológicos y de secuencias de ADN, sugiere una cercana relación filogenética entre Colima y los géneros que integran la subtribu Tigridiinae. Sin embargo, las relaciones de Colima a nivel genérico no están completamente resueltas por el análisis molecular. Por último, se describe e ilustra una nueva especie del género Colima de El Tuito, Jalisco. En esta última los tallos, pedicelos, ovarios y frutos son alados. Además, los tépalos son de color amarillo-crema, oblanceolados con ápices acuminados y el androgineceo es más pequeño que en Colima convoluta.

Mexico is the diversity center of the genus Tigridia (Tigridieae: Iridaceae). Its irregular topography and climatic diversity have generated a high number of endemics in this group of plants. We conducted collecting expeditions in Mexico during the summers of 1996 and 2000. The goals of the expeditions were to widen the known geographical distribution of Tigridieae and to collect leaf material, bulbs and seeds for phylogenetic studies of this group of plants. As a result, we found new populations of T. bicolor Molseed, T. matudae Molseed and T. vanhouttei ssp. roldanii Molseed, in Oaxaca, Morelos, and Puebla respectively. These taxa were known only from their type localities. These new localities are presented together with field observations and aspects of phenology., México es el centro de diversificación del género Tigridia (Tigridieae: Iridaceae). El accidentado relieve y la diversidad climática presentes en el país han favorecido el desarrollo de endemismos en este grupo. En los veranos de 1996 y 2000 se llevaron a cabo colectas botánicas a fin de ampliar el conocimiento de la distribución geográfica de la tribu Tigridieae y obtener semillas, bulbos y hojas para el estudio filogenético del grupo. Como resultado de este trabajo, se localizaron nuevas poblaciones de T. bicolor Molseed, T. matudae Molseed y T. vanhouttei ssp. roldanii Molseed en Oaxaca, Morelos y Puebla respectivamente. Estos taxones solo se conocían de la localidad tipo. Las nuevas localidades se presentan junto con observaciones de campo y aspectos de fenología de las especies.

Tigridia gracielae (Tigridieae: Iridaceae), from the state of México, is a new species morphologically similar to T. venusta, from the state of Michoacán. Tigridia gracielae differs from T. venusta in having shorter and narrower tepals, a longer staminal column, anthers fertile along their full length and shorter style branches. Both species share habitat preference for the shaded understory of fir and pine forests near 3000 m elevation., Tigridia gracielae (Tigridieae: Iridaceae), del Estado de México, es una nueva especie morfológicamente similar a T. venusta, de Michoacán. La primera se distingue de la segunda por presentar tépalos más cortos y angostos, columna más larga, anteras fértiles en toda su longitud y ramas del estilo más cortas. Ambas especies crecen en el estrato inferior de bosques de oyamel y pino a una altitud cercana a los 3000 m.