scholarly journals Colonial nesting waterbirds as vectors of nutrients to Lake Lesser Prespa (Greece)

Inland Waters ◽  
2021 ◽  
pp. 1-17
Author(s):  
Yvon J.M. Verstijnen ◽  
Valentini Maliaka ◽  
Giorgos Catsadorakis ◽  
Miquel Lürling ◽  
Alfons J.P. Smolders
Keyword(s):  
2020 ◽  
Author(s):  
Miki Saijo ◽  
Nobuyuki Kutsukake

AbstractPredation risk exerts a strong selective pressure on anti-predator behavior, resulting in behaviors to achieve defense of offspring and the individual. In shorebirds, some species perform distraction behavior that is attracting the attention of a predator. This behavior evolved, and were lost multiple times, independently and the behavioral repertoire varies among species. Although defense of offspring is critical for parents, the determinants of inter-specific variation in the distraction behavior remain unstudied. We surveyed the literature and conducted phylogenetic comparative analyses (n = 169 species) to test predictions regarding nest site, body mass, and coloniality. We found that small species were more likely to perform distraction behavior than large species. Solitary species were more likely to perform distraction behavior than colonial nesting species. Previous studies suggested that colonial nesting and large species commonly perform aggressive anti-predator behavior, implying that distraction behavior is an alternative anti-predator strategy to aggressive ones.


2022 ◽  
Author(s):  
Robert Muxo ◽  
Kevin Whelan ◽  
Raul Urgelles ◽  
Joaquin Alonso ◽  
Judd Patterson ◽  
...  

Breeding colonies of wading birds (orders Ciconiiformes, Pelecaniformes) and seabirds (orders Suliformes, Pelecaniformes) serve as important indicators of aquatic ecosystem health, as they respond to changes in food abundance and quality, contaminants, invasive species, and disturbance. The Comprehensive Everglades Restoration Plan, Restoration Coordination & Verification program (CERP-RECOVER) has identified wading-bird colonies as an important ecosystem restoration indicator. The National Park Service South Florida/Caribbean Inventory & Monitoring Network (SFCN) ranked colonial nesting birds eighth out of 44 vital signs of park natural resource conditions for ecological significance and feasibility. However, while large-scale monitoring efforts are occurring in the rest of the Greater Everglades Ecosystem, only minimal historic data collection and no extensive ongoing monitoring of wading bird and seabird nesting have occurred in Biscayne National Park. Consequently, due to their high importance as biological indicators and because they are a gap occurring in regional monitoring efforts, the network has initiated a monitoring program of colonial nesting birds in Biscayne National Park. This protocol provides the rationale, approach, and detailed Standard Operating Procedures for annual colonial bird monitoring within and close to Biscayne National Park and conforms to the Oakley et al. (2003) guidelines for National Park Service long-term monitoring protocols. The specific objectives of this monitoring program are to determine status and long-term trends in: Numbers and locations of active colonies of colonial nesting birds with a special focus on Double-crested Cormorants, Great Egrets, Great White Herons, Great Blue Herons, White Ibises, and Roseate Spoonbills. Annual peak active nest counts of colonial nesting birds in Biscayne National Park with a special focus on the species mentioned above. An annual nesting index (i.e., sum of monthly nest counts) with a special focus on the species mentioned above. Timing of peak nest counts for the focal species.


2020 ◽  
Vol 71 (2) ◽  
pp. 238
Author(s):  
Rebecca E. Lester ◽  
Heather M. McGinness ◽  
Amina E. Price ◽  
Ashley Macqueen ◽  
N. LeRoy Poff ◽  
...  

Environmental watering is frequently used to achieve specific ecological objectives, such as triggering spawning or seed germination. These short-term objectives are often met, but longer-term objectives, such as population growth, may not be, especially where multiple hydrological and non-hydrological factors influence success. We propose a framework to identify these factors in space and time. Our framework steps users through identifying possible inhibiting (strictures) and supporting (promoters) factors, and placing these factors in their spatial and temporal context. This allows users to identify potential limiting factors that may require additional intervention, or render the original watering action unsustainable. We illustrate the framework with examples of a floodplain tree (black box, Eucalyptus largiflorens), colonial nesting waterbird (royal spoonbill, Platalea regia) and large-bodied migratory fish (golden perch, Macquaria ambigua). The framework explores strictures and promoters for major life-history stages, emphasising the need to support and protect all stages if objectives include population maintenance or growth. In this way, the framework can document existing mental models and can be used as the basis of a risk portfolio, a prioritisation tool or future quantitative models. Thus, the framework enables individual management actions to be better grounded in a broader context, increasing the likelihood of achieving long-term ecological objectives.


The Condor ◽  
2019 ◽  
Vol 121 (4) ◽  
Author(s):  
Chad B Wilsey ◽  
Nicole L Michel ◽  
Katie Krieger ◽  
Lotem Taylor ◽  
Liling Lee ◽  
...  

Abstract The Tricolored Blackbird (Agelaius tricolor) is a range-restricted, colonial-nesting species in decline. Colonies include tens of thousands of individuals that forage in the surrounding landscape, at times commuting miles between nesting and foraging grounds. We explored the role of landscape composition on colony occupancy and mapped core and potential spring foraging habitat in California, USA. We used observations of spring Tricolored Blackbird nesting colonies from 2008, 2011, and 2014 and characterized changes in the surrounding landscape during an extended drought. Then, we constructed occurrence and abundance models in order to map core foraging habitat across 4 ecoregions in California. Finally, we used simulated land cover changes to identify potential habitat under restoration scenarios. Across the 3 survey years, surface water declined over time at unoccupied colony locations but remained stable at occupied colony locations, confirming that permanent surface water was a critical feature of persistent Tricolored Blackbird colonies. Average percent cover of nearly all land cover types suitable for foraging, as well as frequency of dairies and median NDVI, were all higher in current or historical colony sites than elsewhere. The proportion of surrounding alfalfa, grasslands, and surface water were the elements of foraging habitat best able to predict Tricolored Blackbird early breeding season colony presence and colony size. Core foraging habitat covered over 6 million acres in the study region, but only 18% was occupied in 2014. This result suggests a need to study additional factors determining colony occurrence and persistence, such as landscape connectivity, distributions of nesting substrates, and risk from predators. The vast majority (93.1%) of Tricolored Blackbird core habitat occurred on private land; therefore, saving the species will require engagement and partnership with private landowners.


Sign in / Sign up

Export Citation Format

Share Document