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The surfaces of alluvial fans and river deltas (collectively fans) are often dissected by a small number of channels radiating from the fan apex. On long timescales, channels migrate via avulsion, the process of channel bed deposition and abandonment that often results in catastrophic flooding and loss of life on densely populated fans. We present results of an experimental fan that creates realistic channel patterns by avulsion. The avulsion cycle occurs with a period that is predictable from conservation of mass. Selection of a new flow path is inherently stochastic; however, once a network of 4–5 channels is established, flow oscillates among these channels indefinitely. We demonstrate that a directed random walk model with memory quantitatively reproduces these dynamics and limiting behavior, and is consistent with natural fans.

Obtaining robust estimates of population abundance is a central challenge hindering the conservation and management of many threatened and exploited species. Close‐kin mark‐recapture (CKMR) is a genetics‐based approach that has strong potential to improve the monitoring of data‐limited species by enabling estimates of abundance, survival, and other parameters for populations that are challenging to assess. However, CKMR models have received limited sensitivity testing under realistic population dynamics and sampling scenarios, impeding the application of the method in population monitoring programs and stock assessments. Here, we use individual‐based simulation to examine how unmodeled population dynamics and aging uncertainty affect the accuracy and precision of CKMR parameter estimates under different sampling strategies. We then present adapted models that correct the biases that arise from model misspecification. Our results demonstrate that a simple base‐case CKMR model produces robust estimates of population abundance with stable populations that breed annually; however, if a population trend or non‐annual breeding dynamics are present, or if year‐specific estimates of abundance are desired, a more complex CKMR model must be constructed. In addition, we show that CKMR can generate reliable abundance estimates for adults from a variety of sampling strategies, including juvenile‐focused sampling where adults are never directly observed (and aging error is minimal). Finally, we apply a CKMR model that has been adapted for population growth and intermittent breeding to two decades of genetic data from juvenile lemon sharks (Negaprion brevirostris) in Bimini, Bahamas, to demonstrate how application of CKMR to samples drawn solely from juveniles can contribute to monitoring efforts for highly mobile populations. Overall, this study expands our understanding of the biological factors and sampling decisions that cause bias in CKMR models, identifies key areas for future inquiry, and provides recommendations that can aid biologists in planning and implementing an effective CKMR study, particularly for long‐lived data‐limited species. Here, we investigate the sensitivity of close‐kin mark‐recapture (CKMR) models to violations of underlying assumptions, and then propose and test modified approaches that correct the bias. We find that base‐case CKMR models are sensitive to unmodeled population dynamics and measurement error including interannual fluctuations in population size, intermittent breeding dynamics, and aging error. We then present adapted models that account for the hidden population dynamics, and – using both simulation and real genetic data – show that targeted sampling of juveniles that can be reliably aged can eliminate the bias that arises from errors in aging.

ABSTRACT Objective: The Bonefish Albula vulpes is a popular sport fish found throughout the tropical western Atlantic Ocean. In south Florida, concerns have been raised over population decline of this species, primarily attributed to the degradation of their nearshore habitats. While foraging and spawning habitat types have been identified and protective actions taken, early life history habitat associations for Bonefish have yet to be described. The presence of more broadly distributed cryptic congeners, A. goreensis and undescribed A. cf. vulpes, also with undefined habitat preferences, has complicated previous efforts. The objective of this study was to leverage long-term state agency monitoring of Florida estuaries to describe and parse nursery habitats for Albula spp. to better inform monitoring and conservation efforts targeted towards recovering and protecting the Bonefish fishery. Methods: We summarized spatiotemporal patterns, environmental tolerances, and habitat associations. We used a generalized additive model to identify realized habitat and community associations within the Indian River Lagoon. Data were sourced from the Florida Fish and Wildlife Conservation Commision statewide Fisheries-Independent Monitoring program. Post-time series and unassociated sampling provided specimens for genetic species identification and allowed for the descriptions to be applied with species-level context. Results: From 1996 to 2019, 522 juvenile and 124 larval Albula spp. were caught using multiple gears, with more than half the catches coming from the Indian River Lagoon. Albula spp. were most frequently captured over sand and mud bottom habitats with no vegetation or low-structure sea grass (shoal grass Halodule wrightii). Juveniles were tolerant of substantial variability in water conditions throughout Florida estuaries, and ranges modeled for the Indian River Lagoon were temperatures of 21.3–33.5°C, dissolved oxygen of 2.2–13.7 mg/L, and salinity of 18.0–38.9‰. Within the Indian River Lagoon, catch per unit effort increased significantly from 2011 onward, coinciding with a mass sea grass die-off event. Similar to described Bonefish community dynamics in The Bahamas, heterospecific interactions with mojarra Eucinostomus spp. were observed, while novel associations with marine penaeid shrimp Farfantepenaeus spp. are due to a combination of biological and physical processes. Species genetically identified were dominated by A. goreensis. Conclusions: The described and modeled estuarine habitat preferences throughout Florida are most representative of A. goreensis, though Bonefish and A. cf. vulpes co-occurred in some samples. Bonefish nursery habitat in Florida continues to be unidentified at a scale that would support the Bonefish fishery, maintaining that more effort is needed to describe its habitat use throughout Florida. Lay Summary The Bonefish is a culturally and economically important sport fish throughout south Florida. In recent years, population decline has been identified in fishing guide logbooks, eliciting community concern and consideration for drivers of decline that may affect the population throughout their life history. Nursery habitats in Florida have yet to be identified or described for Bonefish or other co-occurring relatives, thus hampering conservation actions. Thirty-three years of estuary sampling by the Florida Fish and Wildlife Conservation Commission produced only 646 young-of-the-year bonefishes, highlighting the rarity of successful recruitment for the genus, let alone the Bonefish that support the fishery. Our findings establish the strong presence of Albula goreensis throughout Florida estuaries, though Bonefish may co-occur and do so further north than their recognized range, thus possibly linking the south Florida Bonefish fishery to estuaries further north through migration as fish mature. To holistically address conservation concerns for the south Florida Bonefish fishery, more diversified efforts must be targeted at locating and describing Bonefish nurseries.

Assuming that the sediment flux in the Exner equation can be linearly related to the local bed slope, we establish a one-dimensional model for the bed-load transport of sediment in a coastal-plain depositional system, such as a delta and a continental margin. The domain of this model is defined by two moving boundaries: the shoreline and the alluvial–bedrock transition. These boundaries represent fundamental transitions in surface morphology and sediment transport regime, and their trajectories in time and space define the evolution of the shape of the sedimentary prism. Under the assumptions of fixed bedrock slope and sea level the model admits a closed-form similarity solution for the movements of these boundaries. A mapping of the solution space, relevant to field scales, shows two domains controlled by the relative slopes of the bedrock and fluvial surface: one in which changes in environmental parameters are mainly recorded in the upstream boundary and another in which these changes are mainly recorded in the shoreline. We also find good agreement between the analytical solution and laboratory flume experiments for the movements of the alluvial–bedrock transition and the shoreline.

Packed with indelible portraits of individual artists and informed by John Swenson's encyclopedic knowledge of the city's unique and varied music scene, New Atlantis is a stirring chronicle of the valiant efforts to preserve the culture that gives New Orleans its grace and magic. The book follows some of New Orleans's most gifted musicians--including such figures as Dr. John, the Neville Brothers, \"Trombone Shorty,\" and Big Chief Monk Boudreaux--as they fight back against a tidal wave of problems.

This book critically addresses the potential of the liberal concept of collective security to provide a solution to conflict in East Asia, with a focus on the Korean peninsula.

The use of technology has already impacted the practices of mental health professionals. For example, websites are utilized to advertise and provide information to prospective clients. Cell phones, email, and websites are used to quickly make and cancel appointments as well as take payments. Taking the next step of utilizing a range of telemental health services can greatly increase the counseling services offered by mental health professionals while meeting the needs of underserved populations. However, necessary considerations must be made to provide these services in an ethical manner. In this article, we summarize the ethical codes from the major mental health professions as they pertain to telemental health, and we also offer practical suggestions as to how to expand one's practice while offering telemental health services according to the highest ethical standards. We will focus primarily on discussing ethical standards as they pertain to videoconferencing.

An epizootic of sarcoptic mange was prevalent among Scandinavian red foxes (Vulpes vulpes) during the late 1970s and 1980s. By substantially reducing the population density of foxes, the epizootic created a natural experiment on the importance of fox predation for prey density. The fox population started to recover during the late 1980s. We monitored the populations of the fox and its prey [voles (Cricetidae), mountain hare (Lepus timidus), European hare (L. europaeus), Capercaillie (Tetrao urogallus), Black Grouse (T. tetrix), Hazel Grouse (Bonasa bonasia), and roe deer (Capreolus capreolus)] throughout the event, on a local (10¹—10² km²), a regional (10⁴ km²), and a national scale. Methods included den counts, snap—trapping, pellet/dropping counts, counts of displaying birds, young/adult ratio from incidental observations of deer, regional questionnaires, and national hunting records. The study revealed red fox predation as a crucial factor in limiting the numbers of hares and grouse as well as fawns per doe of roe deer in autumn, and in conveying the 3—4 yr cyclic fluctuation pattern of voles to small game. The classical view, that predators take but a doomed surplus of their prey, was false for these species in Scandinavia.