Northwest Science - Accepted Articles and Notes
Northwest Science 98(2)
Intertidal and subtidal marine succession rates on new rock armor in Chiniak Bay, Kodiak, Alaska - E. Leyla Arsan, Tom Lance, Kelly Krueger, Rebecca Shaftel
Alaska has 33,904 miles of coastline and most coastal infrastructure in the state is armored for erosion protection, yet little is known about colonization or recolonization rates post-disturbance in high northern latitudes. This study quantifies the recruitment and colonization of new armor rock at the Kodiak Airport and documents algal and sessile invertebrate species abundance and assemblage (percent cover) at the airport and at reference sites with similar substrates, salinity, wave exposure, and depth. Over four years of annual intertidal and subtidal monitoring, average percent cover by algae and invertebrates at study sites ranged from 13 % to 100 %. Study sites showed extensive cover by early colonizing algae and invertebrates in both the intertidal and subtidal at 15 months post-construction silt curtain removal (Year 1). Prominent biobanks of monospecies (e.g., bay mussels [Mytilus trossulus]) observed in Year 1 largely changed to barnacles (Balanus sp.) and algal species by Year 4. Both algal cover and number of species increased over time at study sites; total cover and number of species were similar to reference sites by Year 4. The colonization rate of rock armor and the successional timeframe to develop full ecological functions are important because of the potential effects of rock armor on aquatic habitats, at both local and landscape scales. This study illustrates that colonization of new armor rock in southcentral Alaska can be rapid (can average 80.8% cover of intertidal and subtidal substrates after 1 year) and that interannual variability of species abundance may occur throughout the successional cycle.
Northwest Science 98(1)
Early development of Pacific surf smelt (Hypomesus pretiosus) - Kathleen G. Neely, Mark Tagal
We observed development in surf smelt embryos from 24 hours post fertilization through hatch, at water temperature 12.52 oC (SD = 0.22) – 22.37 oC (SD = 1.14). Our system mimicked the tidal cycle by draining incubation chambers of water for twelve hours a day in concert with a photoperiod that mimicked seasonal light/dark cycle of 16 hours light and 8 hours of darkness. First detected heartbeat was documented at 62 degree days, partial hatch occurred on 187 degree days and all remaining live eggs had hatched by 225 degree days. Developmental milestones were documented with micro photography and videography. Various developmental stages were illustrated in pen and ink for documentation. This work was used to gather developmental baseline data for the species.
Native ponderosa pine at Joint Base Lewis-McChord, Washington - Jeffrey R. Foster
Joint Base Lewis-McChord, WA, has the largest population of ponderosa pine (Pinus ponderosa) west of the Cascade Range in the Pacific Northwest. Field mapping showed a modern geographic range of ≈ 13,270 ha. The ages and locations of the largest, oldest pines indicated that at the time of EuroAmerican settlement in the mid-1800’s, most pines grew in a single area of ≈ 1,730 ha within a landscape of woodland, savanna, and grassland maintained by Native American fire. After settlement ended burning, conifer forest replaced much of the original vegetation and the range of pine expanded. I repeatedly measured permanent plots over an 11-yr period (2007‒2018) within the two forest types with pine: Closed Forest (canopy cover ≥ 60 %), dominated by Douglas-fir (Pseudotsuga menziesii), and Woodland/Savanna (cover 5–59 %), often mixed with Douglas-fir and Oregon white oak (Quercus garryana). Pine basal area and density were similar between types. Overstory pines in Woodland/Savanna had larger diameter growth and crown ratio, lower height and height:diameter ratio, and averaged 40 yr younger, than those in Closed Forest. Pine regeneration was scarce in both forest types. The only notable temporal trends were increasing Douglas-fir regeneration density in Closed Forest and log accumulation in Woodland/Savanna. Pine diameter and age distributions showed an increasing deficit of young pines over time. Major impediments to pine regeneration are fires that burn hotter than historically and competition from a non-native shrub, Scotch broom (Cytisus scoparius). Active management will be necessary to perpetuate this pine population, at least in Woodland/Savanna.
The complete pre-print version of this article is available here.
Seasonal and diel movements of adult yellow perch between two contrasting lakes (Lake Union and Lake Washington) in the Seattle metropolitan area/USFWS-SOTS - Roger A. Tabor, Daniel W. Lantz, Lauren S. Urgenson, Aaron Bosworth, Eric J. Warner, Jeffery R. Johnson
We examined the seasonal movements of adult yellow perch (Perca flavescens) between a small, shallow lake (Lake Union) and a large, deep lake (Lake Washington). Lake Union is the largest part of the Lake Washington Ship Canal (LWSC), a narrow waterway between Lake Washington and Puget Sound. Yellow perch were implanted with acoustic tags that had a battery life of at least 460 days. All tagged yellow perch were captured and released in Lake Union in the summer of 2020 or 2021. Movements were monitored primarily with 14 stationary receivers that were deployed at key locations between the two lakes. Additional information was obtained from mobile tracking and other stationary receivers in Lake Washington. Of the 47 fish tagged, we were able to get seasonal movement data on 28 fish. Twenty-three (82 %) of them left Lake Union and moved into Lake Washington while the other five (18 %) remained in the LWSC. Most movements from Lake Union to Lake Washington occurred in September or October when water temperatures were decreasing. Return movements from Lake Washington to Lake Union had variable timing. Migrations between Lake Union and Lake Washington usually took just a few hours and took place day or night. The farthest observed distance moved from the release site was approximately 16 km. Within Lake Washington, tagged yellow perch were found over a broad area in the northern two/thirds of the lake. Overall, tracking results indicated yellow perch can make extensive migrations between the two lakes.
The complete pre-print version of this article is available here.
Does surface-applied biochar alter insect utilization of downed ponderosa pine (Pinus ponderosa) bolts? - Stacey Rice-Marshall, John Randall, Stephen P. Cook
Biochar can be used as a soil amendment to restore degraded soils, sequester carbon, and increase soil water holding capacity and plant available water following harvest operations in a forest. On-site production and utilization of biochar is being explored as a forest management tactic. One benefit of the practice is the sequestration of C from unmerchantable forest biomass to produce biochar. Forest insects may be exposed to biochar when the material is applied to surface organic horizons and downed trees. How biochar affects insects’ ability to locate and utilize downed woody material in the forest is undetermined. Two field experiments, with freshly downed sections (bolts) of ponderosa pine (Pinus ponderosa Lawson & C. Lawson), were conducted to determine the potential impact of applied biochar on insect communities utilizing the bolts. In the first experiment, bolts were baited with a pheromone lure and biochar applied at a rate equivalent to 2,914 Kg ha-1 (1.30 tons acre-1). The biochar treatment did not interfere with attack or emergence of the pine engraver Ips pini (Say) (Coleoptera: Curculionidae: Scolytinae) compared to untreated control bolts. In the second experiment, biochar applied at a rate equivalent to 5,604 Kg ha-1 (2.50 tons acre-1) lowered species richness compared to non-treated bolts. In addition, one species, red turpentine beetle, Dendroctonous valens (LeConte) (Coleoptera: Curculionidae: Scolytinae) were more abundant in non-treated bolts compared with biochar-treated bolts. Utilization of bolts by other insect taxa such as longhorn beetles (Coleoptera: Cerambycidae) was similar in non-treated and biochar-treated bolts.
The complete pre-print version of this article is available here.
Comparison of lapilli otoliths and pectoral fin rays for estimating age of Northern Pikeminnow - Caleb M. Wilson, Bryce Marciniak, Mike Thomas, Jordan Messner, Matthew P. Corsi, Michael C. Quist
Northern Pikeminnow Ptychocheilus oregonensis is a piscivorous cyprinid native to western North America. Information on the best structure for estimating age of Northern Pikeminnow is a key knowledge gap that may limit inquiries on management efforts. Thus, the objective of this study was to evaluate between-reader precision and concordance between age estimates for lapilli otoliths and pectoral fin rays from Northern Pikeminnow. Age estimates from lapilli otoliths were compared to those from pectoral fin rays of 150 Northern Pikeminnow captured from Lake Cascade, Idaho, in April-May 2022. Exact percent-agreement of estimated ages between the readers was higher for fin rays (75.3 %) than otoliths (50.0 %), with a mean coefficient of variation of 3.5 and 8.7, respectively. Readers also assigned a confidence rating (0-3; higher value reflects higher confidence in age estimate) to each structure. Confidence ratings were higher for fin ray age estimates (mean ± SD; 1.6 ± 0.6) than otolith estimates (1.1 ± 0.7) across readers. A consensus age was estimated for each structure and fish. Agreement between consensus age estimates for otoliths and fin rays was 26.7 % with a coefficient of variation of 14.0. Our findings suggest that fin rays were easier to collect, process, and read than otoliths, and resulted in more precise age estimates than otoliths. Results from our study provide guidance on the best structures for estimating the age of Northern Pikeminnow that can be used to inform management efforts.
The complete pre-print version of this research note is available here.
Demography and habitat associations of the basalt cactus: Pediocactus nigrispinus - Zarha S. Dillon-Zuppelli, Mary E. Poulson, Eric A. Graham
Cacti are iconic members of arid ecosystems. Pediocactus nigrispinus is a species of cactus endemic to the Pacific Northwest and has been listed as a sensitive species due to its vulnerability to habitat loss. Best conservation methods for this species are poorly understood, due in part to a limited understanding of its demography and habitat associations that may help define its occurrence. A demographic study in Washington state was implemented in 2016 to provide a baseline of the population dynamics for P. nigrispinus and to enhance conservation efforts for this sensitive species. Five years of size, fecundity, and survival information for the cactus were recorded. A stochastic analysis was performed to assess survival and fecundity rates for different climatic variables. To better understand the cacti’s limited habitat, biotic and abiotic associations were assessed in an additional 16 plots throughout Washington and Oregon by spatial analysis of soil and climatic variables and in situ assessment of vegetation and ground cover associations. These variables were then compared with population density, overall size of the individuals, and number of fruits to assess how changes in associations may correlate with changes in these population traits. The demographic study found no juvenile recruitment and a declining population over the four years of analysis regardless of variation in annual precipitation. The association analysis found no correlation between population density or fecundity with associations but indicated higher fruit production in Oregon than in Washington.
The complete pre-print version of this article is available here. Below, a matrix model showing average stage transitions for a five-year demographic study of a Pediocactus nigrispinus in Washington state. All stages can interact year to year, but those proportions are all very small (<5 %). Values within circles indicate stasis. Dotted arrows indicate fecundity. Stasis was the primary vital rate for every size class of cactus.
