Northeastern New Research Articles

Constraining regional scale fault architecture in the southern New England Orogen: integration of seismic, multiscale edges and surface mapping

SUMMARY Regional scale fault structures are considered a first order control on hydrothermal ore systems. Recognition and delineation of such features is essential for search space reduction and project selection in exploration. The New England Orogen in northeastern New South Wales has significant potential for the discovery of new hydrothermal ore systems. However, limits to interpretation of broad scale geophysics in the region and limited exposure for ground-based mapping have hampered the recognition of the first order fault architecture in many areas. As part of the Geological Survey of New South Wales 3D mapping program, we aim to further the understanding of strike extensive and depth penetrative regional scale fault architecture in the southern New England Orogen. The workflow for constraining the regional 3D fault architecture involves integrating a limited number of deep seismic lines with broader gravity and magnetic waveletbased multiscale edges. All the geophysical data sets are further constrained by the Geological Survey of New South Wales’ seamless geology mapping and surface structural orientation data. The work to date demonstrates correlation between the lateral position of multiscale edges and their dip inferred from upward continuation, with steeper dipping structures interpreted in seismic lines. Strike orientations of edges, or systematic breaks in edges, are broadly consistent with structural orientations previously recognised in mapping, but often not at the true regional scale as suggested by edge continuity. Known hydrothermal ore systems in the southern New England Orogen display a strong correlation with the deeply penetrating edges.

A taxonomic revision of the Phrynosoma douglasii species complex (Squamata: Phrynosomatidae).

Short-horned lizards (Phrynosoma douglasii species complex) occur throughout the inter-montane West and Great Plains of western North America. The comparative morphology and color pattern variation of short-horned lizards was studied in 3,174 specimens. Multivariate analyses of 20 morphological and color-pattern characters were applied to 977 specimens, and univariate statistics were summarized for 52 samples totaling 1,134 specimens. The results of the morphological data analyses support the recognition of P. douglasii (Bell 1828) as a distinct species, and the resurrection of P. brevirostris Girard 1858a and P. ornatissimum Girard 1858a as species distinct from P. hernandesi Girard 1858a. Two new species allied to P. brevirostris are described: P. bauri sp. nov. from the eastern plains of Colorado and northeastern New Mexico, southeastern Wyoming and southwestern Nebraska south of the North Platte River, and P. diminutum sp. nov. endemic to the San Luis Valley of southern Colorado and northern New Mexico. The Mexican taxon brachycercum Smith 1942 is reassigned as a subspecies of P. ornatissimum, based on non-discrete character differences and overall morphometric similarity. The ranges of P. hernandesi and P. ornatissimum broadly overlap in central New Mexico, the former taxon occupying the coniferous forests of disjunct mountain ranges, the latter occuring in the surrounding desert grasslands. Principal components analysis has revealed morphological evidence of hybridization where the two taxa meet, generally within ecotones between montane forest associations and grasslands. Principal components analysis has also revealed a high level of morphological variability in populations occurring in the Colorado Plateau region of northeastern Arizona, northwestern New Mexico, extreme southwestern Colorado and adjacent Utah. The evidence suggests that these populations arose through past hybridization between the two species. The taxon ornatum Girard 1858b, although sharing several traits with P. brevirostris, is morphologically close to P. hernandesi. It is regarded as a stabilized population of hybrid origin, but treated taxonomically as a subspecies of P. hernandesi. The taxonomic arrangement in this study, with the exception of P. douglasii, is largely discordant with the proposed taxonomy from a previously published study based on mitochondrial DNA sequence data.

Descriptions of three new species of Glossogobius (Teleostei: Gobiidae) from New Guinea

Three new species of Glossogobius are described from New Guinea. Glossogobius multipapillus, n. sp. from northeastern New Guinea has a lobed mental fraenum and a distinctive papilla pattern unlike any other species in the genus. Glossogobius sentaniensis, n. sp. is described from Lake Sentani. The species is similar to Glossogobius aureus and G. koragensis differing in head pores and large dark spots on the body. Glossogobius macrocephalus n. sp. from Lake Tebera and surrounding rivers has a lobed mental fraenum and differs from other species in the Glossogobius celebius group in the combination of having a large head, head pore, fin-ray and predorsal scale counts.

Interinstitutional Variability in Testicular Volumes and Varicocele Presence by Ultrasound: Surprising Discrepancies and Implications for Clinical Decision Making

To determine the variability of testicular ultrasound (US) volumes and the clinical implications. A retrospective review identified 73 patients (62 adult and 11 adolescents) who had testicular US scans performed at both our institution (Urological Institute at Northeastern New York) and at an outside facility (outside hospital study). Testicular volume (TV) was measured using the Lambert formula: length × width × height × 0.71. TV difference (TVD) was calculated as percentage difference = 100 × (right TV - left TV)/left TV and serves as the intrapatient TVD. Patients with clinically palpable varicoceles were correlated to detection on US. Bland-Altman plots were generated to compare the limits of agreement for interinstitutional TVs. Interinstitutional agreement was measured using the Kappa (κ) coefficient. Although the mean values for TVs were similar between institutions (19.1 vs 19.0 cm(3)), there was a wide range in the limits of agreement with a large standard deviation of difference (8.52 cm(3)). Interinstitutional agreement was poor regarding patients with a ≥ 20% TVD (κ = 0.09) and was even worse in patients with both varicoceles and ≥ 20% TVD (κ = 0.05). US agreement for verification of clinically detected varicoceles was good (κ = 0.67). If the variability found in this study was applied to identically sized testicles, an erroneous 20% TVD would be found in 38% of studies. Interinstitutional or inter-ultrasonographer assessment of TV varies significantly. Clinicians should cautiously interpret the US-determined TV when making surgical decisions. Images, and not just reports, should be reviewed by clinicians.

Novitates neocaledonicae I: An additionnal new species of Planchonella (Sapotaceae) endemic to the Roches de la Ouaième

A new species of Planchonella, endemic to the Roches de la Ouaième in northeastern New Caledonia, is described and illustrated. Planchonella ulfii morphologically resembles P. roseoloba, while molecular data indicate a closer relation to P. minutiflora and P. koumaciensis, with all three species belonging to a clade characterized by ridged fruits. The new species brings the total for the genus to 37 species in New Caledonia, 36 of which are endemic to the archipelago. With a single known population comprising 10 individuals, a preliminary risk of extinction assessment using the IUCN Red List criteria indicates that it is Critically Endangered due to risk of fire faced by the shrubby vegetation found of the summit crest of the Roches de la Ouaième. The level of micro-endemism found at this site is discussed.

Release of constraints on nest-site selection in burrow-nesting petrels following invasive rat eradication

Introduced mammals have been eradicated from many offshore islands around the world, removing predation pressure from burrow-nesting seabirds and other affected wildlife. Nest-site selection in procellariiform seabirds is mediated by nesting habitat characteristics and social information, although it is unclear if, or how, nest-site selection will affect post-eradication colony growth. Using a Bayesian hierarchical modeling approach we assessed how nest-site selection differs among burrow-nesting seabird colonies at different stages of recovery after Pacific rat (Rattus exulans) eradication. We compared nest-site selection in a community of seven procellariiform species among six offshore islands in northeastern New Zealand: four designated rat-free over a continuum within the last 26 years, an island which never had rats, and an island with rats present. We hypothesized that, immediately after eradication, birds would be constrained to nesting habitat where they were less vulnerable to predation, and as time since eradication increased birds would eventually spread to new habitat. We found a positive relationship between mean burrow density and time since rat eradication. Soil depth was the most important predictor of burrow presence, abundance, and occupancy in plots among islands, with more burrows found in deeper soil. We found that the relationships between habitat covariates and nest-site selection decreased with increasing time since eradication. The probability of a covariate having a significant effect on nest-site selection decreased with increasing time since eradication and decreasing variability in the covariate across an island. Our results suggest that the eradication of rodents reduced constraints on petrel nesting distribution and that nest-site selection in burrow-nesting petrels may be influenced by burrow density, where selection of particular nesting habitat characteristics may be relatively more important in small recovering populations. We conclude that colony expansion immediately after predator removal is complex, influenced by numerous interacting factors, but may be partly limited by the availability of suitable nesting habitat.

Coralline turf-associated fauna are affected more by spatial variability than by host species identity

We examined the effects of host species identity and spatial variability on animals inhabiting subtidal coralline algal turfs, by comparing the assemblages of small (1–8 mm) mobile invertebrates associated with five coralline turf species across a number of subtidal rocky reefs in northeastern New Zealand. Coralline turf fauna were abundant (average of 16,000 to 80,000 ind.m−2) and diverse (129 taxa in total), with assemblages dominated by arthropods, gastropods and polychaetes. Despite substantial differences in the morphologies of the coralline turf species, host identity had little effect on total abundance and richness of the fauna, and a moderate effect on taxonomic composition. Spatial variation at the scale of 102–103 m had a stronger influence than host identity on all three assemblage-level properties, with wave exposure and depth having the most explanatory power of the environmental factors measured. Host-specificity was low, probably due to the close taxonomic relatedness of the host algal species and their inedibility (with consequent lack of dietary specialisation by fauna). For our study system, the results justify the common practice of lumping coralline turf species in ecological studies with regard to the description of the total abundance and richness of the associated fauna, but not the taxonomic composition of the fauna.

Ungulate exclusion, conifer thinning and mule deer forage in northeastern New Mexico

The southwestern United States has experienced expansion of conifer species (Juniperus spp. and Pinus ponderosa) into areas of semi-arid grassland over the past century. The expansion of conifers can limit palatable forage and reduce grass and forb communities. Conifer species are sometimes thinned through hydraulic mulching or selective cutting. We assessed the effects of these treatments on mule deer (Odocoileus hemionus) habitat in northeastern New Mexico to determine if conifer thinning improved cover of preferred forage species for mule deer in areas with and without ungulates. We measured plant cover and occurrence of preferred forage species in the summers of 2011 and 2012. An ongoing regional drought probably reduced vegetation response, with preferred forage species and herbaceous cover responding to conifer thinning or ungulate exclusion immediately following treatment, but not the following year. In 2011, areas that received thinning treatments had a higher abundance of preferred forage when compared to sites with no treatment. Grass coverage exhibited an immediate response in 2011, with ungulate exclosures containing 8% more coverage than areas without exclosures. The results suggest that conifer thinning and ungulate exclusion may elicit a positive response, however in the presence of drought; the positive effects are only short-term.

Four Finisterre-Huon languages: An introduction

Abstract The verbal categories of Finisterre-Huon Papuan languages Awara, Ma Manda, Nek, and Nungon are typologically remarkable in several ways. Their tense systems have multiple subdivisions within past and future tenses. Tense is fused with number, but the number system varies depending on tense, with the most number values distinguished in the future tenses. Immediate and delayed imperatives are distinguished, with the immediate imperative implying brusqueness and the delayed imperative implying politeness. Aspect is generally encoded analytically, with auxiliary verb constructions, although some languages mark habitual aspect through a verbal suffix. Surprisingly, medial verbs may mark more aspectual distinctions than final verbs. Finally, although grammatical evidentiality is not widely known to exist in Papuan languages of northeastern New Guinea, non-firsthand evidentiality is found to be entwined with verbal aspect marking in both Awara and Nungon. The four Finisterre-Huon (FH) Papuan languages represented in this volume – Awara, Ma Manda, Nek, and Nungon – bring to light many of the unique typological characteristics of this group of under-described languages. The papers presented here offer a sense of the commonalities and differences found in the verbal inflectional systems of FH languages. This introduction provides general background on FH languages, and summarizes some of the points of convergence and divergence among the languages discussed in this volume.

Tree-Ring Dating of Historic Buildings in Willsboro, Northeastern New York, and Development of Regional Chronologies for Dendroarchaeology

Historical timbers have been sampled from buildings at 13 sites in Willsboro, New York, on the west shore of Lake Champlain. Ring-width series from 139 timbers have been successfully crossdated and used to develop tree-ring chronologies for ash (Fraxinus spp.), oak (Quercus spp.), pine (Pinus spp.), eastern hemlock (Tsuga canadensis (L.) Carr.), and spruce (Picea spp.), which collectively span A.D. 1555 to 1878. Tree cutting dates suggest that Windyview Manor was likely built in or soon after 1799, and a barn and farmhouse at the 1812 Homestead were built in or soon after 1812 and 1813, respectively. These dates are all consistent with documentary records for these sites. Aggregate data for the town suggest a shift in wood use for building during the 19th Century, with ash and oak commonly used for large frame timbers from the 1790s to 1820s, and hemlock and spruce dominating from the 1830s to 1860s. Chronologies developed in this project are among the first from historical timbers for northern New York and will facilitate further dendroarchaeological work in the region.

The international nature of the Miramichi Fire

The forest fire that swept across New Brunswick and Maine on 7 October 1825 is remembered as one of the largest and most devastating ones in recorded history, and the first great fire of North American settlement. Yet as its name suggests, the Miramichi Fire has been understood almost exclusively in local terms; historical accounts written in the U.S. or Canada even tend to ignore the blaze that burned on the other side of the border. The following essay, while focusing on the fire that burned along the Miramichi region of northeastern New Brunswick, restores the fire's international character, showing that what might first seem the embodiment of a local event—a chemical process responsive to hyper-local climatic, botanical, and even topographical conditions—was ultimately shaped by and in turn shaped natural and cultural events around the globe. The essay specifically explores how unusual climatic conditions in the late 1810s and early 1820s altered the fire regime of northeastern New Brunswick. The region's inhabitants, the great majority of whom were recent immigrants with little experience of the forests and fires of eastern North America, were unprepared for what was to come.

Comparison of morphological variation among parthenogeneticAspidoscelis neomexicana, gonochoristicA. Sexlineata viridis, and their hybrids (Squamata: Teiidae) from Ute Lake and Conchas Lake, northeastern New Mexico

Abstract Meristic morphological variation among samples of A. neomexicana, A. sexlineata viridis, and their hybrids from Ute and Conchas lakes, New Mexico, was assessed to determine if evidence of separate introductions resided in differences in A. neomexicana between the two localities. However, there were no significant differences between samples of A. neomexicana (and between samples of A. sexlineata viridis) based on multivariate statistical analyses of eight meristic characters. Paradoxically, hybrids from the two localities were significantly different in principal components 1 and 2 and in pigmentation. Hybrids from Ute Lake were paler than hybrids from Conchas Lake and A. neomexicana from both localities. All hybrids could be visually distinguished from A. neomexicana by the absence of thin transverse gray bands on the ventral surface of the tail and closer paravertebral stripes.

Flows in the Tasman Front south of Norfolk Island

The Tasman Front is a narrow band of eastward flowing subtropical water crossing the Tasman Sea from Australia to North Cape, New Zealand. It is the link between the two subtropical western boundary currents of the South Pacific, the East Australian Current (EAC) off eastern Australia, and the East Auckland Current (EAUC) off northeastern New Zealand. Here we report the first direct measurements of flow in the Tasman Front from a moored array deployed across gaps in the submarine ridges south of Norfolk Island and hydrographic and ADCP measurements during the deployment and recovery voyages. The mean flow through the array over July 2003 to August 2004 was found to be eastward only in the upper 800 m with a transport of ∼6 Sv. Below 800 m a weak westward mean flow (∼1.5 Sv) was measured, associated with Antarctic Intermediate Water (AAIW). Using sea surface height to account for additional transport south of the moored array results in a total mean eastward transport between Norfolk Island and North Cape, New Zealand of ∼8 Sv, varying between −4 and 18 Sv. The measurements show that the Tasman Front is much shallower than either the EAC or EAUC, both of which extend below 2000 m depth, has less transport than either the EAC or EAUC and has instances of flow reversal. Thus, the Tasman Front is a weaker connection between the EAC and EAUC than the paradigm of a contiguous South Pacific western boundary current system would suggest.

Characterization of a flood-associated deposit on the Waipaoa River shelf using radioisotopes and terrigenous organic matter abundance and composition

An ephemeral oceanic-flood deposit adjacent to a well-studied small mountainous river (SMR), the Waipaoa River in northeastern New Zealand, was characterized using multiple proxies, including radioisotopes (234Th, 7Be, and 210Pb), bulk organic carbon abundance and isotopic signature (%OC, δ13C), as well as a biomarker of terrigenous organic matter (lignin). Field sampling was conducted within two weeks after a 1-in-8 year flood that occurred between January 30 and February 6, 2010. Geochemical analyses indicated that initial deposition of fresh riverine material extended alongshore to the north and south from the river mouth. A comparison of prior- and post-flood 7Be inventories revealed that flood sediments were widely dispersed between 20 and 70m water depth, accounting for 50–80% of the estimated flood load. Surface (0–2cm) isotopic carbon values increased with distance from Poverty Bay, positively correlating with total 210Pb activities, potentially reflecting increasing marine influence with water depth. Abundances of sedimentary organic carbon (OC) were 0.18–0.76% dry weight, and the total nitrogen varied from 0.02 to 0.13%. Stable isotope signatures of carbon (δ13COC), nitrogen (δ15N), and lignin abundances (λ6) throughout the study area ranged from −23.6 to −27.7‰, 1.9 to 5.3‰, and 0.93 to 9.0mg 100mg OC−1, respectively. The spatial distribution pattern of terrigenous organic matter (OM) abundance and interclass ratios (indicative of freshness of organic matter) varied along and across-shelf. Lignin abundances were high and interclass ratios were low in the southern depocenter and inner shelf areas, suggesting that this zone had recently received vascular-plant enriched OM, minimally altered by shelf-bed mixing processes. In contrast, sediments in the northern depocenter and outer shelf also contained elevated amounts of terrigenous sedimentary OM, but this material was generally lower in lignin abundance and had higher interclass ratios (greater degradation). Collectively, these results suggest that the flood-derived sediment and fresh terrigenous OM were mostly constrained between 20 and 70m water depth, with enhanced deposition overlapping the tectonic-controlled depocenters located to the northeast and southeast of Poverty Bay.

Genetic diversity in native and introduced populations of the amethyst gem clam Gemma gemma (Totten, 1834) from the U.S. east and west coasts

Reduced genetic diversity due to founder effects often is expected for invasive populations. The present study examined two nuclear gene regions and one mitochondrial gene to evaluate the origins and genetic diversity of Gemma gemma, a ‘stow-away’ that was introduced to California more than 100 years ago with the importation of the Eastern oyster, Crassostrea virginica, from the United States’ Atlantic coast. A previous investigation involving mitochondrial DNA cytochrome-c-oxidase subunit I sequences reported no significant difference in haplotype diversity between the native and introduced populations; however, estimates of allelic (or haplotypic) variability are insensitive to losses of rare alleles that may accompany founder events and population bottlenecks. Estimates of allele richness and the distribution of rare alleles provide more sensitive indicators of such events. The present investigation of introduced and potential source populations identified lower allele richness and number of singleton alleles in California samples. Atlantic coast Gemma exhibit a sharp phylogeographic transition between northeastern (New York through New England) and mid-Atlantic (southern New Jersey through Virginia) subpopulations, which appear latitudinally inverted for the California Gemma populations. These genetic results, and information from the transportation history of the Eastern oyster, help to clarify processes involved in the introduction of this invasive species.

The influence of habitat availability on juvenile fish abundance in a northeastern New Zealand estuary

Management of fish populations is often focused on the exploitation of adult fish. Maintaining the habitat requirements of all life stages may also be an important consideration. We investigated the value of structured habitat to juvenile fishes within a northeastern New Zealand harbour using artificial seagrass units (ASUs). Specifically, we deployed ASUs across treatments with high vs. low habitat manipulations. We hypothesised that if the abundance of recruiting juvenile fishes was greater on the high habitat availability treatments this would suggest that the availability of habitat was limiting juvenile fish abundance. Our analyses were focused on the four most abundant fishes that settled on our ASUs: snapper (Pagrus auratus); spotty (Notolabrus celidotus); trevally (Pseudocaranx dentex); and an assemblage of pipefish species. For snapper, spotty and pipefish, abundance was greater on the high habitat availability treatments. This result would be unlikely to occur if the availability of juvenile fishes was limiting, suggesting that juvenile fish abundance is more likely to be limited by habitat. In terms of spatial gradients, spotty abundance and size increased with distance into the harbour. The spatial gradient present for spotty indicates the importance of placing the habitat dependency of juvenile fish into a landscape context. Overall, these results demonstrate that maintaining structured habitats may be an important consideration for some valuable inshore fish populations in northeastern New Zealand.

The smallest Cyrtoscydmini of Australia: revision of Microscydmus Saulcy & Croissandeau and Penicillidmus gen. n.(Coleoptera, Staphylinidae, Scydmaeninae).

The Australian members of Microscydmus are revised, and a new subgenus Scydmomicrus subgen. n. is established to accommodate seven species: M. (Sc.) australiensis Franz (type species of Scydmomicrus), M. (Sc.) nasicornis Franz, M. (Sc.) capitiseboraci sp. n., M. (Sc.) queenslandicus sp. n., M. (Sc.) styxianus sp. n., M. (Sc.) edithensis sp. n., and M. (Sc.) tooloomensis sp. n. A new Microscydmus-like genus, Penicillidmus gen. n., is described to include Penicillidmus masseyensis sp. n. (type species of Penicillidmus) and P. unicolor sp. n. Species of Microscydmus and Penicillidmus are distributed along the eastern coast of Australia, from the northern Cape York to northeastern New South Wales, and females of an undescribed Microscydmus are recorded from southern New South Wales. The revised taxa comprise the smallest Australian Cyrtoscydmini, with body lengths of only 0.50-0.65 mm (Microscydmus) and 0.83-0.86 mm (Penicillidmus). For comparative purposes, morphological details of the type species of Microscydmus, M. nanus, are described, and structures of the new subgenus and new genus are illustrated. Variations of character states within Microscydmus found among Australian species are discussed.

Effects of marine reserves in the context of spatial and temporal variation: an analysis using Bayesian zero-inflated mixed models

Evaluating the effects of marine reserves on exploited species can be challenging because they occur within a context of natural spatial and temporal variation at many scales. For rigorous inferences to be made, such evaluations require monitoring programmes that are repli- cated at appropriate scales. We analysed monitoring data of snapper Pagrus auratus (Sparidae) in northeastern New Zealand, comprised of counts from baited-underwater-video surveys from inside and outside 3 marine reserves. Surveys were replicated at many levels, including areas inside and outside of marine reserves at 3 locations in 2 seasons, over a period of up to 14 yr, in an unbalanced design. The Bayesian modelling approach allowed the use of some familiar aspects of ANOVA, including mixed models of fixed and random effects, hierarchically nested structures, and variance decomposition, while allowing for overdispersion and excess zeros in the counts. Model selection and estimates of variance components revealed that protection by marine reserves was by far the strongest measured source of variation for relative densities of legal-sized snapper. The size of the effect varied across years among the 3 reserves, with relative densities between 7 and 20 times greater in reserves than in nearby areas. Other than the reserve effect, the temporal factors of season and year were generally more important than the spatial factors at explaining variation in counts. In particular, overall relative densities were ~2 to 3 times greater in autumn than in spring for legal-sized snapper, although the seasonal effect was also variable among locations and years. We consider that the Bayesian generalised linear mixed modelling approach, as used here, provides an extremely useful and flexible tool for estimating the effects of management actions and comparing them directly with other sources of spatial and temporal variation in natural systems.

A Non-Destructive Method for Dating Human Remains

AbstractThe skeletal remains of several Native Americans were recovered in an eroded state from a creek bank in northeastern New Mexico. Subsequently stored in a nearby museum, the remains became lost for almost 36 years. In a recent effort to repatriate the remains, it was necessary to fit them into a cultural chronology in order to determine the appropriate tribe(s) for consultation pursuant to the Native American Grave Protection and Repatriation Act (NAGPRA). Because the remains were found in an eroded context with no artifacts or funerary objects, their age was unknown. Having been asked to avoid destructive dating methods such as radiocarbon dating, the authors used Optically Stimulated Luminescence (OSL) to date the sediments embedded in the cranium. The OSL analyses yielded reliable dates between A.D. 1415 and A.D. 1495. Accordingly, we conclude that the remains were interred somewhat earlier than A.D. 1415, but no later than A.D. 1495. We believe the remains are from individuals ancestral to the Ute Mouache Band, which is now being contacted for repatriation efforts. Not only do our methods contribute to the immediate repatriation efforts, they provide archaeologists with a versatile, non-destructive, numerical dating method that can be used in many burial contexts.

Signals of watershed change preserved in organic carbon buried on the continental margin seaward of the Waipaoa River, New Zealand

Abstract Holocene sediments buried on the continental shelf seaward of the Waipaoa River, northeastern New Zealand, preserve a stratigraphic record of terrestrial environmental change. The well characterized, long-term record of storms, volcanism, and human disturbance in this region provides an opportunity to examine how such changes are reflected in the character of organic carbon (OC) buried on the continental margin. Complimentary evidence obtained from analyses of the 14 C content and the elemental and stable carbon isotopic composition of different sedimentary fractions, including charcoal, wood, and clay-sized isolates, indicates that these perturbations led to mobilization of OC components with variable storage histories in the watershed. Charcoal transported in the modern Waipaoa River and buried in offshore depocenters includes a highly aged component that has apparently been slowly released from storage in soil or alluvial terraces. The charcoal fraction ages become dramatically younger in sediments deposited after the Taupo volcanic eruption (1717 cal yr BP) and then Polynesian settlement (ca. 700 cal yr BP), both signaling biomass burning. The mean age of woody plant fragments and clay-bound OC deposited on the shelf also varies over time, with older material having accumulated in the middle Holocene and since human occupation. Deposition of older-than-average wood fragments and clay-bound OC between about 5 and 3.6 kyr BP correlates with evidence for a period of increased storm frequency in the region and may reflect the enhanced delivery of aged soil and sedimentary rock mobilized from hill slopes via earthflows and/or deep seated landslides. Similarly, the deposition of older wood and clay-bound OC commensurate with the first anthropogenic disturbance ca. 700 years ago is consistent with accelerated mass wasting due to deforestation. At the same time, a change in the elemental and stable isotopic composition of bulk and clay-bound OC buried on the shelf may reflect increased marine primary productivity and/or mobilization of OC from deep levels in soil profiles. Deforestation of the Waipaoa headwaters by European settlers beginning in the middle 19th century is evinced by a sharper rise in the age of clay associated OC buried offshore. Today, deep gully incision into fractured sedimentary bedrock is a major source of sediment and kerogen to the river, and this process has left its mark on the age of sedimentary OC delivered to the adjacent margin.