Biography:

In the past Robyn Hannigan has collaborated on articles with Bindu Kaimal and Leonette Cox. One of their most recent publications is Distinguishing breeding populations of mallards (Anas platyrhynchos) using trace elements. Which was published in journal Journal of Geochemical Exploration.

More information about Robyn Hannigan research including statistics on their citations can be found on their Copernicus Academic profile page.

Robyn Hannigan's Articles: (4)

Distinguishing breeding populations of mallards (Anas platyrhynchos) using trace elements

AbstractThe knowledge of connectivity among breeding and overwintering populations of migratory bird species is critical for the conservation of their habitats. Conventional field work for the tracking of migratory birds involving bird banding often yields poor results due to low recovery rates, or is expensive when satellite tracking methods are used. Intrinsic tools such as genetic markers, stable isotopes, strontium isotopes and trace elements have been successfully used for tracing origins and/or migratory pathways of bird populations. We studied elemental signatures in the tail feathers to group breeding populations and an overwintering population of Mallards (Anas platyrhynchos). Tail feathers from five locations in Canada and the U.S. were analyzed using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). We used 18 elements to discriminate between Mallard populations. Linear discriminant analysis on a selected set of elements demonstrated that 93% of the Mallards could be accurately located back to their predicted locations. Mallard feathers from Arkansas (an important overwintering area), grouped together with any combination of elements as predictors. We predicted the breeding locations of overwintering Mallards from Arkansas. Our results confirm that the LA-ICP-MS technique shows high potential to estimate the origin of migratory animals.

Distinguishing breeding populations of mallards (Anas platyrhynchos) using trace elements

AbstractThe knowledge of connectivity among breeding and overwintering populations of migratory bird species is critical for the conservation of their habitats. Conventional field work for the tracking of migratory birds involving bird banding often yields poor results due to low recovery rates, or is expensive when satellite tracking methods are used. Intrinsic tools such as genetic markers, stable isotopes, strontium isotopes and trace elements have been successfully used for tracing origins and/or migratory pathways of bird populations. We studied elemental signatures in the tail feathers to group breeding populations and an overwintering population of Mallards (Anas platyrhynchos). Tail feathers from five locations in Canada and the U.S. were analyzed using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). We used 18 elements to discriminate between Mallard populations. Linear discriminant analysis on a selected set of elements demonstrated that 93% of the Mallards could be accurately located back to their predicted locations. Mallard feathers from Arkansas (an important overwintering area), grouped together with any combination of elements as predictors. We predicted the breeding locations of overwintering Mallards from Arkansas. Our results confirm that the LA-ICP-MS technique shows high potential to estimate the origin of migratory animals.

Chapter 1 What goes around comes around: Today's environmental geochemistry

AbstractWhat is environmental geochemistry? Is it simply the application of geochemical techniques to environmental media such as water or soil? Is it the study of contaminants and pollutants? Is it all low temperature geochemistry exclusive of the biosphere and natural weathering processes? For certain the definition is complex. The field is clearly diverse as is evidenced in this book. Indeed this book best represents the complexity of the field, a snapshot, if you will, of concepts and applications in the field. Bearing in mind that the field is ever changing, a dynamic and evolving discipline, we provide a brief historical perspective and an attempt to define today's environmental geochemistry.

Chapter 33 Black shale weathering contribution to stream chemistry using end-member mixing analysis

AbstractA mathematical approach known as end-member mixing analysis (EMMA) was applied to determine the end-member components (overland/shallow subsurface, runoff, and groundwater) contributing to the surface water chemistry of two first-order headwater tributaries of the Little Red River in Arkansas. Binary mixing between two end-members explained only a portion of the variance in major anion and cation chemistry of the surface waters. Therefore, ternary mixing was investigated using the EMMA method. Previous studies using EMMA have involved first- and second-order streams of various bedrock types. This study is unique in that it is the first, to our knowledge, to apply this approach to the study of first-order streams draining black shales. The tributaries we investigated (Cove Creek and Begley Creek) are underlain mainly by metal-rich Mississippian Fayetteville Shale. Weathering of this bedrock could affect water quality. Where surface waters are in intimate contact with these shales, it is necessary to determine the extent to which these waters contribute to the chemistry of the stream as a first approximation to the significance of black shale weathering to the catchment.The mixing analysis results suggest that the contributions from overland/shallow subsurface flow, runoff from the black shale outcrop, and groundwater play a major role in making up the surface water chemistry of Begley and Cove Creeks under both storm and base flow conditions. The relative contribution of these end-members varies with flow. As expected, the mixing results showed that groundwater dominates during base flow. During storm flow the surface water chemistry represents a mix of overland/shallow subsurface flow and black shale runoff. We found that during storm flow groundwater and overland/shallow subsurface flow were, in general, indistinguishable across storm hydrographs resulting in storm flow chemistries represented by binary mixtures of two chemically distinct end-members. Ion concentration ratios are similar for overland/shallow subsurface flow and groundwater because of the lithologic similarities of the rocks in contact with these waters. Runoff from the black shale outcrop does contribute to the surface water chemistry.

Advertisement
Join Copernicus Academic and get access to over 12 million papers authored by 7+ million academics.
Join for free!

Contact us