scholarly journals Response of colonial Peruvian guano birds to flying UAVs: effects and feasibility for implementing new population monitoring methods

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e8129 ◽  
Author(s):  
Cinthia Irigoin-Lovera ◽  
Diana M. Luna ◽  
Diego A. Acosta ◽  
Carlos B. Zavalaga
Keyword(s):  
Behavioral Response ◽  
Population Monitoring ◽  
Monitoring Methods ◽  
Vertical Descent ◽  
Peruvian Coast ◽  
Speed Range ◽  
Colonial Seabird ◽  
Breeding Condition ◽  
Sula Variegata ◽  
Bird Colonies

Background Drones are reliable tools for estimating colonial seabird numbers. Although most research has focused on methods of improving the accuracy of bird counts, few studies have evaluated the impacts of these methods on bird behavior. In this study, we examined the effects of the DJI Phantom 3 drone approach (altitude, horizontal and vertical descent speeds) on changes in the intensity of behavioral response of guano birds: guanay cormorants (Phalacrocorax bougainvilli), Peruvian boobies (Sula variegata) and Peruvian pelicans (Pelecanus thagus). The breeding and non-breeding condition was also evaluated. Methods Eleven locations along the Peruvian coast were visited in 2016–2017. Drone flight tests considered an altitude range from 5 to 80 m from the colony level, a horizontal speed range from 0.5 to 15 m/s, and a vertical descent speed range from 0.5 to 3 m/s. The intensity of the behavioral response of birds was scored and categorized as: 0-no reacting, 1-head pointing to the drone (HP), 2-wing flapping (WF), 3-walking/running (WR) and 4-taking-off/flying (TK). Drone noise at specific altitudes was recorded with a sound meter close to the colony to discriminate visual from auditory effects of the drone. Results In 74% of all test flights (N = 507), guano birds did not react to the presence of the drone, whereas in the remaining flights, birds showed a sign of discomfort: HP (47.7%, N = 130), WF (18.5%), WR (16.9%) and TK (16.9%). For the drone approach tests, only flight altitude had a significant effect in the intensity of the behavioral response of guano birds (intensity behavioral response <2). No birds reacted at drone altitudes above 50 m from the colony. Birds, for all species either in breeding or non-breeding condition, reacted more often at altitudes of 5 and 10 m. Chick-rearing cormorants and pelicans were less sensitive than their non-breeding counterparts in the range of 5–30 m of drone altitude, but boobies reacted similarly irrespective of their condition. At 5 m above the colony, cormorants were more sensitive to the drone presence than the other two species. Horizontal and vertical flights at different speeds had negligible effects (intensity behavioral response <1). At 2 m above the ground, the noise of the cormorant colony was in average 71.34 ± 4.05 dB (N = 420). No significant differences were observed in the drone noise at different flight altitudes because the background noise of the colony was as loud as the drone. Conclusions It is feasible to use the drone DJI Phantom 3 for surveys on the guano islands of Peru. We recommend performing drone flights at altitudes greater than 50 m from guano bird colonies and to select take-off spots far from gulls. Likewise, this study provides a first step to develop guidelines and protocols of drone use for other potential activities on the Peruvian guano islands and headlands such as surveys of other seabirds and pinnipeds, filming and surveillance.

Detecting, counting and following the giants of the sea: a review of monitoring methods for aquatic megavertebrates in the Caribbean

2019 ◽  
Vol 46 (7) ◽  
pp. 545
Author(s):  
D. N. Castelblanco-Martínez ◽  
M. P. Blanco-Parra ◽  
P. Charruau ◽  
B. Prezas ◽  
I. Zamora-Vilchis ◽  
...  
Keyword(s):  
Critical Role ◽  
Critical Evaluation ◽  
Population Monitoring ◽  
Tourism Industry ◽  
Caribbean Region ◽  
Monitoring Methods ◽  
Photo Identification ◽  
Important Region ◽  
The Caribbean ◽  
Marine Megafauna

Abstract The Caribbean is a mega-diverse and bio-geographically important region that consists of the Caribbean Sea, its islands, and surrounding coastlines. Among the billions of aquatic species inhabiting this region, the mega-vertebrates stand out for their social, economic and ecologic relevance. However, the Caribbean has been threatened by climate change, poverty, pollution, environmental degradation and intense growth of the tourism industry, affecting megafauna species directly and indirectly. Population monitoring plays a critical role in an informed conservation process and helps guide management decisions at several scales. The aim of the present review was to critically examine the methods employed for monitoring marine megafauna in the Caribbean, so as to create a framework for future monitoring efforts. In total, 235 documents describing protocols for the monitoring of sirenians, cetaceans, elasmobranchs, sea turtles and crocodilians in the Caribbean region, were reviewed. The methods included community-based monitoring (interviews, citizen science and fisheries monitoring), aerial surveys (by manned and unmanned aerial vehicles), boat-based surveys (including manta tow, and side-scan sonars), land-based surveys, acoustic monitoring, underwater surveys, baited remote underwater video, mark–recapture, photo-identification and telemetry. Monitoring efforts invested on aquatic megafauna in the Caribbean have been highly different, with some species and/or groups being prioritised over others. The present critical review provides a country-based overview of the current and emerging methods for monitoring marine megafauna and a critical evaluation of their known advantages, disadvantages and biases.

scholarly journals Learning to count: adapting population monitoring for Endangered huemul deer Hippocamelus bisulcus to meet conservation objectives

2020 ◽  
Author(s):  
Heiko Wittmer ◽  
P Corti ◽  
C Saucedo ◽  
J Galaz
Keyword(s):  
Survey Data ◽  
Survey Methods ◽  
Cost Effective ◽  
Population Monitoring ◽  
Population Trends ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Hippocamelus Bisulcus ◽  
Detection Probabilities ◽  
Current Survey

Considerable efforts have been invested in recent years to improve methods for both data collection and analyses required for population monitoring. Where historical or current estimates of population size are not adjusted for detection probabilities they may be too inaccurate to provide meaningful estimates of trends and thus monitoring methods need to be adapted. Here, we use data from the Endangered huemul deer Hippocamelus bisulcus to outline a framework to develop accurate robust estimates of detection probabilities that can be incorporated into new surveys in a cost-effective way and applied to existing survey data sets. In particular, by retroactively estimating detection probabilities for surveys of huemul, we show that current survey methods for huemul are inadequate to determine population trends reliably. Based on these results we propose a new monitoring method for the huemul and discuss the importance of estimating accuracies of historical survey data to ensure that changes in the abundance of the species reflect real population trends and are not an artefact of variation over time in the accuracy of survey data. © 2010 Fauna & Flora International.

scholarly journals Learning to count: adapting population monitoring for Endangered huemul deer Hippocamelus bisulcus to meet conservation objectives

2020 ◽  
Author(s):  
Heiko Wittmer ◽  
P Corti ◽  
C Saucedo ◽  
J Galaz
Keyword(s):  
Survey Data ◽  
Survey Methods ◽  
Cost Effective ◽  
Population Monitoring ◽  
Population Trends ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Hippocamelus Bisulcus ◽  
Detection Probabilities ◽  
Current Survey

Considerable efforts have been invested in recent years to improve methods for both data collection and analyses required for population monitoring. Where historical or current estimates of population size are not adjusted for detection probabilities they may be too inaccurate to provide meaningful estimates of trends and thus monitoring methods need to be adapted. Here, we use data from the Endangered huemul deer Hippocamelus bisulcus to outline a framework to develop accurate robust estimates of detection probabilities that can be incorporated into new surveys in a cost-effective way and applied to existing survey data sets. In particular, by retroactively estimating detection probabilities for surveys of huemul, we show that current survey methods for huemul are inadequate to determine population trends reliably. Based on these results we propose a new monitoring method for the huemul and discuss the importance of estimating accuracies of historical survey data to ensure that changes in the abundance of the species reflect real population trends and are not an artefact of variation over time in the accuracy of survey data. © 2010 Fauna & Flora International.

scholarly journals Multi-surveyor detection-mark-redetection as a powerful tool for butterfly population monitoring in the pre-imaginal stage

2022 ◽  
Author(s):  
Heiko Hinneberg ◽  
Jörg Döring ◽  
Gabriel Hermann ◽  
Gregor Markl ◽  
Jennifer Theobald ◽  
...  
Keyword(s):  
Population Monitoring ◽  
Population Estimates ◽  
Life Stages ◽  
Monitoring Methods ◽  
Model Assumption ◽  
Clear Cut ◽  
Detection Probabilities ◽  
Nymphalid Butterfly ◽  
Butterfly Population ◽  
Sessile Organisms

1. For many elusive insect species, which are difficult to cover by standard monitoring schemes, innovative monitoring methods are needed to gain robust data on population trends. We suggest a monitoring of overwintering larvae for the endangered nymphalid butterfly Limenitis reducta. 2. We tested one removal and three detection-mark-redetection (DMR) approaches in a field study in the “Alb-Donau” region, Germany. We replaced movement of the study organisms by random movement of multiple different surveyors, and we examined the model assumption of equal detectability using simulations. 3. Our results indicate that multi-surveyor removal/DMR techniques are suitable for estimating abundance of overwintering L. reducta larvae. Detection probabilities varied with surveyor experience and the uncertainty of population estimates increased with a decrease in personnel expenditure. Estimated larval densities on a spruce clear-cut ranged between one and three individuals per 100 m². 4. We suggest a detection-mark-redetection (DMR) approach with three trained surveyors for the monitoring of L. reducta populations in the pre-imaginal stage. Besides L. reducta, the proposed method is likely to be suitable for other insect taxa with specific immobile life-stages and some sessile organisms, e.g. corals, elusive plants, or fungi.

scholarly journals Learning to count: adapting population monitoring for Endangered huemul deer Hippocamelus bisulcus to meet conservation objectives

Oryx ◽  
2010 ◽  
Vol 44 (4) ◽  
pp. 516-522 ◽  
Author(s):  
Heiko U. Wittmer ◽  
Paulo Corti ◽  
Cristián Saucedo ◽  
José Luis Galaz
Keyword(s):  
Survey Data ◽  
Survey Methods ◽  
Cost Effective ◽  
Population Monitoring ◽  
Population Trends ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Hippocamelus Bisulcus ◽  
Detection Probabilities ◽  
Current Survey

AbstractConsiderable efforts have been invested in recent years to improve methods for both data collection and analyses required for population monitoring. Where historical or current estimates of population size are not adjusted for detection probabilities they may be too inaccurate to provide meaningful estimates of trends and thus monitoring methods need to be adapted. Here, we use data from the Endangered huemul deer Hippocamelus bisulcus to outline a framework to develop accurate robust estimates of detection probabilities that can be incorporated into new surveys in a cost-effective way and applied to existing survey data sets. In particular, by retroactively estimating detection probabilities for surveys of huemul, we show that current survey methods for huemul are inadequate to determine population trends reliably. Based on these results we propose a new monitoring method for the huemul and discuss the importance of estimating accuracies of historical survey data to ensure that changes in the abundance of the species reflect real population trends and are not an artefact of variation over time in the accuracy of survey data.

Fish Assemblages in Large Tropical Reservoirs: Overview of Fish Population Monitoring Methods

2016 ◽  
Vol 24 (2) ◽  
pp. 160-177 ◽  
Author(s):  
Anne Tessier ◽  
Stephane Descloux ◽  
Raymond Lae ◽  
Maud Cottet ◽  
Pierre Guedant ◽  
...  
Keyword(s):  
Fish Assemblages ◽  
Population Monitoring ◽  
Fish Population ◽  
Monitoring Methods ◽  
Tropical Reservoirs

scholarly journals Individual and Temporal Variation in Inland Flight Behavior of Marbled Murrelets: Implications for Population Monitoring

The Condor ◽  
2004 ◽  
Vol 106 (2) ◽  
pp. 344-353 ◽  
Author(s):  
M. Zachariah Peery ◽  
Steven R. Beissinger ◽  
Scott H. Newman ◽  
Benjamin H. Becker ◽  
Esther Burkett ◽  
...  
Keyword(s):  
Population Size ◽  
Population Monitoring ◽  
Breeding Population ◽  
Flight Behavior ◽  
Brachyramphus Marmoratus ◽  
Regional Population ◽  
Breeding Condition ◽  
The Mean ◽  
Para Determinar ◽  
Marbled Murrelets

AbstractWe studied the inland flight behavior of 46 radio-marked Marbled Murrelets (Brachyramphus marmoratus) in 2000 and 2001 in central California to determine how the frequency of inland flights varied among individuals and over time. All breeding murrelets regularly flew inland (mean 82% of daily surveys), but we observed considerable variation in the inland flight behavior of non-nesters. Non-nesters that were physiologically in breeding condition (potential breeders) regularly flew inland (90% of individuals; mean 41% of daily surveys), but non-nesters that were not in breeding condition (nonbreeders) rarely flew inland (20% of individuals; mean 1% of daily surveys). The mean percentage of surveys on which individual murrelets flew inland increased from 20% in 2000 to 61% in 2001, which was partly due to an increase in the percentage of breeders from 11% in 2000 to 50% in 2001. The frequency of inland flights was greatest during the incubation and chick- provisioning stages (100% in both stages), and lowest during the pre- and postbreeding stages (70% and 78%, respectively). Although the mean percentage of flights increased dramatically between years, the regional population estimate from at-sea surveys increased only 28% from 496 to 637 individuals during the same period, indicating that monitoring techniques such as radar that count inland flights are more likely to reflect annual variation in breeding effort than changes in regional population size. Moreover, the inland flight behavior of potential breeders indicates that radar surveys will overestimate breeding population size, even though the lack of inland flights by nonbreeders indicates that radar surveys will underestimate regional population size.Variación Individual y Temporal en el Comportamiento de Vuelo Tierra Adentro de Brachyramphus marmoratus: Implicancias para el Monitoreo de PoblacionesResumen. Estudiamos el comportamiento de vuelo tierra adentro de 46 individuos de Brachyramphus marmoratus marcados con radio transmisores durante el 2000 y 2001 en California central para determinar cómo la frecuencia de vuelos tierra adentro varió entre individuos y a lo largo del tiempo. Todos los individuos reproductivos de B. marmoratus volaron regularmente tierra adentro (media 82% de los muestreos diarios), pero observamos considerable variación en el comportamiento de vuelo tierra adentro en los individuos que no nidificaban. Los individuos que no nidificaban pero que se encontraban fisiológicamente en condición reproductiva (reproductores potenciales) volaron regularmente tierra adentro (90% de los individuos; media 41% de los muestreos diarios), pero los individuos que no nidificaban y que no se encontraban en condición reproductiva raramente volaron tierra adentro (20% de los individuos; media 1% de los muestreos diarios). El porcentaje medio de los muestreos en los cuales los individuos de B. marmoratus volaron tierra adentro incrementó de un 20% en el 2000 a un 61% en el 2001, lo que se debió parcialmente a un incremento en el porcentaje de individuos reproductivos de un 11% en el 2000 a un 50% en el 2001. La frecuencia de vuelos tierra adentro fue mayor durante las etapas de incubación y suministro de alimento a los pichones (100% en ambas etapas), y fue menor durante las etapas pre- y post-reproductivas (70% y 78%, respectivamente). Aunque la proporción media de vuelos incrementó dramáticamente entre años, la población regional estimada a partir de muestreos en el mar incrementó sólo 28% de 496 a 637 individuos durante el mismo período, indicando que las técnicas de monitoreo como el radar, que cuentan los vuelos tierra adentro, tienen una mayor probabilidad de reflejar la variación anual en el esfuerzo reproductivo que en los cambios de tamaño poblacional regional. Más aún, el comportamiento de vuelo tierra adentro de los reproductores potenciales indica que los muestreos con radar sobrestimarán el tamaño poblacional reproductivo, a pesar de que la falta de vuelos tierra adentro por parte de individuos no reproductivos indica que los muestreos con radar subestimarán el tamaño poblacional regional.

scholarly journals Genotyping-in-thousands by sequencing (GT-seq) of non-invasive fecal and degraded samples: a new panel to enable ongoing monitoring of Canadian polar bear populations

2021 ◽  
Author(s):  
Kristen Hayward ◽  
Rute Clemente-Carvalho ◽  
Evelyn Jensen ◽  
Peter Van Coeverden de Groot ◽  
Marsha Branigan ◽  
...  
Keyword(s):  
Polar Bear ◽  
Population Monitoring ◽  
Nucleotide Polymorphisms ◽  
Monitoring Methods ◽  
Fecal Samples ◽  
Non Invasive ◽  
Community Based Programs ◽  
Genetic Patterns ◽  
Promising Solution ◽  
Cost Efficient

Genetic monitoring using non-invasive samples provides a complement or alternative to traditional population monitoring methods. However, Next Generation Sequencing approaches to monitoring typically require high quality DNA and the use of non-invasive samples (e.g. scat) is often challenged by poor DNA quality and contamination by non-target species. One promising solution is a highly multiplexed sequencing approach called Genotyping-in-thousands by sequencing (GT-seq), which can enable cost-efficient genomics-based monitoring for populations based on non-invasively collected samples. Here, we develop and validate a GT-seq panel of 324 single nucleotide polymorphisms (SNPs) optimized for genotyping of polar bears based on DNA from non-invasively collected fecal samples. We demonstrate 1) successful GT-seq genotyping of DNA from a range of sample sources, including successful genotyping of 85.7% of non-invasively collected fecal samples determined to contain polar bear DNA, and 2) that we can reliably differentiate individuals, ascertain sex, assess relatedness, and resolve population structure of Canadian polar bear subpopulations based on a GT-seq panel of 324 SNPs. Our GT-seq data reveal similar spatial-genetic patterns as previous polar bear studies but at lesser cost per sample and using non-invasively collected samples, indicating the potential of this approach for population monitoring. This GT-seq panel provides the foundation for a non-invasive toolkit for polar bear monitoring and contribute to community-based programs – a framework which may serve as a model for wildlife management and contribute to conservation and policy for species worldwide.

scholarly journals Seabird temporal composition, abundance and habitat use in Punta La Metalera (Arequipa, Southern Peru)

2021 ◽  
pp. 161-181
Author(s):  
L. M. Vica Taco ◽  
E. Mamani ◽  
C. R. Luque Fernández
Keyword(s):  
Habitat Use ◽  
Community Studies ◽  
Southern Peru ◽  
Structure And Dynamics ◽  
Peruvian Coast ◽  
Bird Group ◽  
Sula Variegata ◽  
And Behavior ◽  
Number Of Individuals ◽  
Near Threatened

Islands, islets, and guano capes provide a unique variety of habitats for seabirds. Their variability determines the structure and dynamics of the community. Studies about the temporal diversity and habitat use of these systems in southern Peru are lacking. The aim of this study was to analyze the abundance, composition, and behavior of seabirds at Punta La Metalera (El Faro) in the province of Islay in the Arequipa region of southern Peru. We recorded a total of 12 species. One of these is endemic to the Peruvian coast (Cinclodes taczanowskii), one is considered in endangered (Spheniscus humboldti), and four have been assigned near threatened status (Phalacrocorax gaimardi, Pelecanus thagus, Sula variegata and Larosterna inca). Some of these birds belong to the guano bird group. Laridae was the most abundant family due to Larosterna inca, which showed the highest number of individuals. Temporal variation showed that species were most abundant in December and January. The habitat was mainly used for resting, preening, and feeding. However, nesting was also recorded for six species. Based on the little information previously available for this region our findings indicate that Punta La Metalera is an important area for the development and reproduction of some of the species recorded.

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