Investigating the Mechanisms Behind Moth Declines: Plants, Land-use and Climate

Moth populations have declined across large areas of north-western Europe since the mid-20th century, mirroring similar declines in other insect groups. The mechanisms behind these declines are likely manifold, but it is believed that agricultural intensification is a key factor. There were two aims of this thesis: (1) to elucidate the mechanisms behind moth decline in the UK, and (2) to determine ways in which farmland habitats could be improved for moths. Counter to expectations, between 1968 and 2016, the declines in total moth abundance were least severe in the most agriculturally intensive areas and were most severe in semi-natural habitats, as well as in urban environments. Species richness, while remaining stable at the national level, declined in only one habitat type: broadleaf woodland. No evidence was found to support the hypotheses that habitat loss, shading of the understory by canopy-closure, or overgrazing by deer had driven these declines within broadleaf woodland. Evidence was found that warm winters negatively impacted moth abundance, but this effect was consistent across all habitats. Although declines were least severe in improved grassland and arable land, the declines in total abundance were significant and ongoing, despite widespread and increasing adoption of agri-environment schemes (AES) since the early 1990s. In this thesis, the role of nectar resources and larval hostplants were explored within AES field margins on arable land, with the aim of determining how these small areas of habitat could be best managed to enhance moth abundance and diversity. It was found that the diversity of moths was greatly increased, and abundance moderately so, when margins were sown with a wide range of wildflowers and grasses, in comparison to only grasses. The evidence suggested that this was due primarily to the provision of larval hostplants, with nectar resources playing a secondary role. Overall, this thesis demonstrates that, in order to improve the environment for moths, AES wildflower margins should be encouraged over and above plain grass margins. This thesis also demonstrates that while agricultural intensification is likely responsible for some of the observed declines in moths, there are other mechanisms, as yet unknown, at work in both semi-natural habitats and urban areas

Are insects declining and at what rate? An analysis of standardised, systematic catches of aphid and moth abundances across Great Britain

1. Although we have known anecdotally that insects have been declining in Great Britain for more than 100 years, insect declines have only been statistically estimated over the last 20 years. Estimation of the rate of those declines is still hotly debated,fuelled by a lack of standardised, systematically collected data. 2. More than 24 million individual moths and aphids collected from 112 light traps and 25 12.2 m suction-traps, respectively, were analysed using mixed models. Our objective was to estimate the long-term trends in both groups based on annual totals recorded every year between 1969 and 2016. 3. The models showed that two paradigms existed: Over 47 years, long-term linear trends showed that moths had declined significantly by −31%, but short-term trends indicated that there were periods of significant decline and recovery in most decades since the 1960s. Conversely, despite aphid annual totals fluctuating widely, this group was in a steady state over the long-term, with a non-significant decline of −7.6%. Sensitivity analysis revealed that moth trends were not driven by a group of abundant species, but the sign of the overall aphid trends may have been driven by three of the most abundant species. 4. The spatial extent of moth trends suggests that they are extremely heterogeneous.Uniquely, moth declines were different among several habitat types, with robust significant declines found in coastal, urban and woodland habitats, but notably not in agricultural,parkland and scrubland habitats. Conversely, aphid trends showed spatial synchrony extending to 338 km, albeit with local variation

Floral enhancement of arable field margins increases moth abundance and diversity

Moth populations have declined across large parts of north-western Europe since the mid-20th century due, in part, to agricultural intensification. Agri-environment schemes (AES) are widely implemented across Europe to protect biodiversity in agricultural landscapes. Grass field margins enriched with wildflowers typically out-perform grass-only margins in terms of increasing insect abundance and diversity. However, the effect of wildflower enrichment on moths remains largely unstudied. Here, the relative importance of larval hostplants and nectar resources for adult moths within AES field margins are investigated. Two treatments and a control were compared: (i) a plain grass mix, the control, (ii) a grass mix enriched with only moth-pollinated flowers, and (iii) a grass mix enriched with 13 wildflower species. Abundance, species richness and Shannon diversity were up to 1.4, 1.8 and 3.5 times higher, respectively, in the wildflower treatment compared to plain grass. The difference in diversity between treatments became greater in the second year. There was no difference in total abundance, richness or diversity between the plain grass treatment and grass enriched with moth-pollinated flowers. The increase in abundance and diversity in the wildflower treatment was due primarily to the provision of larval hostplants, with nectar provision playing a smaller role. The relative abundance of species whose larval hostplants included sown wildflowers increased in the second year, suggesting colonisation of the new habitat. Implications for insect conservation. We show that, at the farm scale, moth diversity can be greatly enhanced and abundance moderately enhanced by sowing diverse wildflower margins, providing these insects with both larval hostplants and floral resources, compared to grass-only margins

Resection of the liver for colorectal carcinoma metastases - A multi-institutional study of long-term survivors

In this review of a collected series of patients undergoing hepatic resection for colorectal metastases, 100 patients were found to have survived greater than five years from the time of resection. Of these 100 long-term survivors, 71 remain disease-free through the last follow-up, 19 recurred prior to five years, and ten recurred after five years. Patient characteristics that may have contributed to survival were examined. Procedures performed included five trisegmentectomies, 32 lobectomies, 16 left lateral segmentectomies, and 45 wedge resections. The margin of resection was recorded in 27 patients, one of whom had a positive margin, nine of whom had a less than or equal to 1-cm margin, and 17 of whom had a greater than 1-cm margin. Eighty-one patients had a solitary metastasis to the liver, 11 patients had two metastases, one patient had three metastases, and four patients had four metastases. Thirty patients had Stage C primary carcinoma, 40 had Stage B primary carcinoma, and one had Stage A primarycarcinoma. The disease-free interval from the time of colon resection to the time of liver resection was less than one year in 65 patients, and greater than one year in 34 patients. Three patients had bilobar metastases. Four of the patients had extrahepatic disease resected simultaneously with the liver resection. Though several contraindications to hepatic resection have been proposed in the past, five-year survival has been found in patients with extrahepatic disease resected simultaneously, patients with bilobar metastases, patients with multiple metastases, and patients with positive margins. Five-year disease-free survivors are also present in each of these subsets. It is concluded that five-year survival is possible in the presence of reported contraindications to resection, and therefore that the decision to resect the liver must be individualized. © 1988 American Society of Colon and Rectal Surgeons

The state of Britain’s larger moths 2021

This report summarises current knowledge of the state of Britain’s c.900 species of larger moths, presenting analyses of long-term change based on millions of records gathered through the Rothamsted Insect Survey (RIS) and National Moth Recording Scheme (NMRS)

Predictors of survival after hepatic resection among patients with colorectal liver metastasis

Studies suggest improved survival following resection of colorectal cancer liver metastases (CLMs). We investigated predictors of survival among patients with CLM who underwent hepatic resection using the SEER-Medicare database to identify patients ⩾65 years diagnosed with CLM, 1991–2003, who underwent hepatectomy. Cox proportional hazards models were used to identify factors associated with survival after hepatectomy. Of 923 patients with CLM who underwent hepatectomy, 514 were stages I–III and developed CLM>6 months after diagnosis (metachronous), and 409 were stage IV with CLM at diagnosis (synchronous). From the date of hepatectomy, 5 year survival was 22%; younger age, being married, female gender, surgery in an NCI-designated cancer centre, fewer comorbidities, fewer positive lymph nodes, and lower grade were associated with improved survival. Both 5-fluorouracil (5FU)-based chemotherapy and hepatic arterial infusion (HAI) of floxuridine-based chemotherapy following hepatectomy improved survival (HR=0.62, 95% CI: 0.50–0.78; HR=0.51, 95% CI: 0.28–0.97, respectively) in the synchronous, but not metachronous, group. The HR for overall mortality was higher in hospitals with a high vs low procedure volume (0.75, 95% CI: 0.58–0.94). A substantial subgroup of patients with CLM who undergo hepatectomy experiences long-term survival. High hospital procedure volume and use of 5FU-based or HAI-based chemotherapy after resection were associated with improved prognosis

Vascular clamping in liver surgery: physiology, indications and techniques

This article reviews the historical evolution of hepatic vascular clamping and their indications. The anatomic basis for partial and complete vascular clamping will be discussed, as will the rationales of continuous and intermittent vascular clamping