Retired Biology Faculty Research, Publications and Presentations

Permanent URI for this collectionhttps://hdl.handle.net/10222/11013

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Open Access
Regeneration of Forest and Barrens after the Spryfield Fire
(2010-09-02) Patriquin, David; Beazley, Richard
This set of annotated photos illustrates the regeneration of vegetation over 16 months after an intense fire that swept through forest and barrens in the vicinity of Spryfield, Nova Scotia on April 30/May 1 of 2009. The fire destroyed twelve homes. The materials were prepared by Richard Beazley and David Patriquin for a talk given at a meeting of the Halifax Field Naturalists (HFN) on September 2, 2010. The text, with a few modifications to suit this format is taken from their report for the Halifax Field Naturalist (HFN's quarterly newsletter). Richard, an outdoor and photography enthusiast, begins the presentation by providing a travelogue-like overview of the landscapes and views of some individual plant species as they began to regenerate after the fire. In turn, David, a retired biologist, examines the mechanisms by which plants regenerate after a fire and discusses some of the implications of living adjacent to or in fire-prone landscapes.
Open Access
Estimation of growth rate, production and age of the marine angiosperm Thalassia testudinum König
(University of Puerto Rico, 1973) Patriquin, David
There is a linear relation between average growth rate and the average maximum leaf length of Thalassia stands. The ratio production-to-standing crop (wet weight including epiphytes) tends to be constant. New foliage leaves are developed at intervals of about 15 days, and by counting of leaf scars, the age, growth rate and production of underground parts can be estimated.
Open Access
Preliminary observations of the status of shallow water reefs at Sandy Island, Carriacou, Grenada
(1996-10-29) Patriquin, David; Hunte, Wayne
Sandy Island is an uninhabited cay lying off the west coast of Carriacou. Surrounded by clear waters and coral reefs, with an extensive white sand beach and quiet water on its south side and a palm canopy on the island, it has long been a treasured spot for Carriacouans. More recently, it has become a favored site for yachters, shore parties from cruise boats and SCUBA divers. Photos of the island are often used as centerpieces of advertisements for the region. Carriacouans have expressed concern about increasingly large losses of the island to erosion during severe storms, and about degradation of the island and the surrounding reefs believed to be associated with the intensified tourist traffic. Proposals have been made to implement a number of conservation measures. A preliminary survey of the nature and health of the shallow water (0-4 m) coral communities, which are the most important in relation to erosion of the island, was conducted on June 20, 1996 . Coral communities in water deeper than 3-4 m on the east and northeast flanks of the island appeared to be in generally good condition, except that there has been some anchor damage of beds of finger coral. The sea bottom on the south protected side of the island where yachts anchor is sand and rock with some beds of finger coral. These beds have been completely destroyed by anchors. Heavy growth of algae in the area is suggestive of nutrient and organic pollution. The east, north and west flanks of the island have been built up by growth of the elkhorn coral, Acropora palmata , in the reef crest zone (0.5-3.5 m). Covered by living thickets of this species when Prof. Patriquin visited the site in 1969, today this zone consists of a now dead, algal covered "elkhorn coral framework". The highly degraded condition of the elkhorn coral is attributable primarily to two diseases which were not of local origin, however, local factors (overfishing and nutrient pollution) may have exacerbated the problem. The elkhorn coral suffered near 100% mortality at many locales in the Caribbean (including Sandy Island) due to an outbreak of "White Band Disease" in the late 70's/early 80's; it has not since recovered, nor have other species filled its niche. The high algal cover is attributable to a second disease epidemic which caused mass mortalities of the long spined black sea urchin (Diadema antillarum ) throughout the Caribbean in 1983/84 . It has only recently begun to be seen in significant numbers again, and only at some locales. Corals are slow growing species which are readily overgrown by faster growing algae when the algae are not regularly grazed by herbivores or when excessive nutrient input stimulates very rapid algal growth. As well as encroaching on corals, the heavy algal growth suppresses settlement of coral larvae on old coral, which helps to perpetuate an algal dominated state. Surgeonfish, parrotfish, and black sea urchins are the most important herbivores in the Caribbean. Intensive fishing reduces the populations of herbivorous fish, leaving the black sea urchin as the principal herbivore. Hence, when the sea urchins died off, algal growth on shallow reefs increased sharply, except where there were still large fish populations. Today at Sandy Island, fish stocks appear to be low and the black sea urchin is just beginning to reestablish. Most of the massive structures formed by elkhorn coral remain at Sandy Island, some still in the original growth position and some broken down, and still provide protection to the island. Over the east and northeast flanks of the island, this old framework is now firmly bound together by encrusting coralline algae and other binding organisms, and is probably quite resistant to further disruption. However, on the northwest and west flanks, exceptionally heavy growth of mat-forming and bushy algae - possibly stimulated by nutrient pollution from yachts - has prevented growth of encrusting organisms, and the framework can be pulled apart by hand. Residents report that recent erosion of the island has been most severe on the northwest sector of the island and occurred when storm waves approached from the northwest; this can be attributed to puncturing of the fragile elkhorn coral framework in that area. In the absence of regeneration or elkhorn coral, it appears likely that Sandy Island would eventually be lost entirely, that this loss would occur mostly through catastrophic events, rather than gradually, and that the catastrophic losses will become increasingly large relative to what's left with each event. In this context, Sandy Island is in a very precarious condition. Unexpectedly, the survey revealed a new population of healthy, living elkhorn coral, probably not more than a few years old, on the east flank of the island. Colonies up to 75 cm maximum linear dimension were observed, in densities of 1-6 colonies per 4 sq meter area. Also in that region, long spined, black sea urchins are abundant, and there is low algal cover of dead coral. Density of living elkhorn coral and of sea urchins in the reef crest zone decline in a gradient from east to west on the north side of the island; correspondingly, algal cover increases, forming thick mats over the old elkhorn coral, towards the west of the island. No living elkhorn coral was observed on the northwest and west flanks. Black sea urchins were observed in only one patch on the west flank; they were maintaining the patch largely free of algae, in marked contrast to the adjacent areas which bore thick algal mats and had no sea urchins. These patterns suggest that re-establishment of elkhorn coral on the east flank was dependent on prior reestablishment of black sea urchins and their grazing down of algae on the old coral. This situation is of considerable interest scientifically, and is especially encouraging in regard to Sandy Island, because if offers the possibility that elkhorn coral is "on its way back". We suggest that the recovery process could be accelerated by establishing" recovery centres" in areas now covered by thick algal mats. This would involve scraping to remove the algal mat, introducing sea urchins to maintain a low cover, and once the urchins have stabilized and algal cover remains low, transplanting elkhorn coral into the sites. Once established, it would be critical that the potential for physical damage to the new colonies by swimmers and boats is reduced to an absolute minimum. Reducing nutrient and organic pollution from yachts and shore parties, and allowing larger standing stocks of herbivorous fishes to develop would further increase the chances of success. Other measures proposed by Carriacouans to protect the integrity of the existing coral populations, such as establishing permanent moorings for boats, limiting numbers of visitors at one time, removing garbage, reducing wave force by sinking a wreck to create an artificial reef off of the northwest flank and increasing the erosion resistance of the island by planting more vegetation, are sensible, and can help the shallow water communities to return to a more healthy and attractive state. The proposed development of the site with an educational focus is a very appropriate initiative. The Sandy Island system, while limited in extent, illustrates most of the major features of healthy Caribbean reefs, and spatially and historically, the major features of reef decline, both natural, and anthropogenic, and of local and non-local origin. It is an excellent "lab" in which to test and develop some new coral reef management techniques which could help to ensure and accelerate the return of elkhorn coral, and probably other species. These features, together with the convenience of access to the site, its symbolic significance as an idyllic tropical isle, and the obvious sentiment of Carriacouans towards Sandy Island make it, potentially, a valuable research and 2/15 educational site. Developed in thjs context, restoration of the Sandy Island reefs could stimulate more broadly based community based restoration and conservation of coral reefs, and provide new economic opportunities.
Open Access
"Migration" of blowouts in seagrass beds at Barbados and Carriacou, West Indies, and its ecological and geological implications
(Elsevier Scientific Publishing Company, 1975) Patriquin, David
Blowouts are grass-free depressions within seagrass beds at Barbados and Carriacou and reported in the literature to be common elsewhere in the Caribbean region. They are typically crescent-shaped in plan view with the convex side seaward, and are characteristic of elevated seagrass beds in regions of moderate to strong wave action. The seaward edge is steep and exposes rhizomes of Thalassia while the leeward edge slopes gently upward onto the seagrass plateau and is usually colonized by Syringodium. The general morphology of the blowouts, the zonation of organisms across them, and the existence at some blowouts of a lag deposit of cobble-sized material at the scarp base continuous with a rubble layer below the seagrass carpet suggested the blowouts "migrate" seaward. Measurements of erosion at the scarp and of advance of Syringodium onto the blowout floor over a period of one year confirmed this. It is estimated that in the region of blowouts anyone point will be recurrently eroded and restabilized at intervals of the order of 5-15 years. Such processes limit successional development of the seagrass beds, disrupt sedimentary structures, and may result in deposits much coarser than those characteristic of the sandy seagrass carpet.
Open Access
Multi-aged old growth red oak stand on the Chebucto Peninsula
(2016-10-20) Patriquin, David; Hill, Nick
A Rapid Appraisal study was conducted July 21-22, 2009 to verify existence of and characterize an old growth red oak stand on Umlah Hill southeast of Oak Hill Lake in the Five Bridge Lakes Wilderness area on the Chebucto Peninsula, Nova Scotia. It had been known years ago by Ralph Wheadon as a NSDNR employee and fire warden for the area. The site was visited again on Sep 3-4, 2011 to look for charcoal in soil profiles. The study was supported in part by Five Bridges Wilderness Heritage Trust. The stand has features of a multi-aged, old growth oak forest with snags and fallen dead in a range of diameters and distinct moose maple and witch hazel subcanopies. The overstory is made up mostly of red oak, some yellow birch, occasional white birch; red maple was common, but tended to be in the subcanopy/overgrown by oak. The stand covers approximately 15 ha. Cores indicate the larger trees are over 100 years of age. We observed scat from mainland moose as well as evidence of the brown bear and many cavities in snags. Some adjacent areas support younger oak stands with some, but not all of these features. Soil profiles revealed charcoal layers in adjacent areas supporting younger oak stands, but not at Umlah Hill, which appears to have escaped area fires by being relatively isolated and surrounded by wetland. Wind induced tree top damage continuously causes decay in the tallest oaks and these produce single tree light gaps and valuable habitat for a suite of snag-dependent wildlife. This mature forest is thus composed not of trees of several centuries old, but of younger trees yet the forest has the same characteristics of typical Old Growth. This type of old growth red oak forest is apparently now rare within the whole range of red oak in North America.
Open Access
The Chebucto Peninsula: A Significant Conservation Area
(www.ourhrmalliance.ca, 2015-08-09) Patriquin, David
The Parks and Protected Areas on the Chebucto Peninsula on Nova Scotia’s Atlantic coast and some of the features that make the whole peninsula a significant conservation area are described and illustrated with maps and photos.
Open Access
Landscapes of the Five Bridge Lakes Wilderness Area: A Natural History
(Woodens River Watershed Environmental Organization, 2010-02-17) Patriquin, David
The Five Bridge Lakes Wilderness Area (FBLWA) lies about 20 kilometers west of downtown Halifax, Nova Scotia. It encompasses 8,626 hectares hectares of Crown land located in the centre of the Chebucto Peninsula on Nova Scotia’s Atlantic coast. This set of photographs, maps, Google Earth images and text provides a virtual tour of the area and interpretation of landscapes from a natural history perspective. The materials were assembled for a presentation at the AGM of the Woodens River Watershed Environmental Organization on February 17, 2010. The FBLWA was formally designated a Wilderness Protected Area under Nova Scotia’s Wilderness Areas Protection Act on Oct 25, 2011.
Open Access
A Rare, Fire-Dependent Pine Barrens at the Wildland-Urban Interface of Halifax, Nova Scotia
(2014-10-06) Hill, Nick; Patriquin, David
Open Access
The State-Spaced Integrated assessment model for Newfoundland's 'northern cod' as a stock assessment model that fails to distinguish between normative and natural laws
(2018-02-06) Corkett, Christopher
Stock assessment models for Atlantic Canada's groundfish fisheries such as Noel Cadigan's recent State-Spaced Integrated assessment model for Newfoundland's 'northern cod' involve single premised inductive arguments that do not distinguish between normative and natural laws. By contrast, management of Canada's inshore Maritime lobster fishery has involved a dual premised deductive argument in the form of a critical dualism in which normative regulations are developed by trial and error, guided by negative feedback from the natural universal law of sustainability. It is my thesis that if Atlantic Canada's groundfish fisheries are to avoid further collapse they will, like the inshore lobster fishery, have to be managed by a critical dualism in which decisions are taken (not made). In this dual premised deductive argument catch limits (quotas) representing normative laws, would be developed by trial-and-error involving the method of 'selection by error elimination' guided by universal natural laws such as the universal law of sustainability, theories that explain what cannot be achieved by the groundfish fishery and what should not therefore be attempted by the fishery as a whole.
Open Access
Reflections on the failure of traditional fisheries management
(2017-01) Corkett, Christopher John
A traditional fisheries management or fish stock assessment takes a Lamarckian-like instructive view of fisheries science that involves an inductive monism. Its invalid inductive arguments have no problem solving capacity and are responsible for the collapse of some of the World's largest Gadoid fisheries including Newfoundland's 'northern cod' in the early 1990s. If we are to solve our management problems, an instructive view of fisheries science will need to be replaced with a problem-solving critical dualism involving downward causation in which (I) norms are chosen by the participants and not predicted as MSYs and MEYs and (ii) a fishery is managed by the method of 'selection by error elimination' guided by 'there-is-not' rules such as the Universal Law of Sustainability. Like me, the ecologist Tony Underwood has developed a Popperian program of research; but here the logical technical term 'falsification' has been viewed from a distance as the word 'false'. This linguistic mistake has had drastic consequences; the discipline of ecology has been turned into a pseudoscience, a non-falsifiable science incapable of guiding the management of a commercial fishery. The absurdicy that a traditional fisheries management should seek instruction from the environment in the form of 'facts' or data instead of subjecting bold tentative policies to a Darwinian-like selection by error elimination, results in a monism of 'scientific' ethics. That is: an ethics in which norms (values) are not chosen by the participants, but are viewed as scientifically achievable predictions.
Open Access
Reflections on the failure of traditional fisheries management
(2016-06-03) Corkett, Christopher
A traditional fisheries management or fish stock assessment takes a Lamarckian-like instructive view of fisheries science. Its invalid inductive arguments have no problem solving capacity and are responsible for the collapse of some of the World's largest Gadoid fisheries including Newfoundland's 'northern cod' in the early 1990s. If we are to solve our management problems; an instructive view of fisheries science will need to be replaced with a problem-solving critical dualism in which (i) norms are chosen by the participants and not predicted as MSYs and MEYs and (ii) a fishery is managed by the method of selection by critical elimination guided by 'there-is-not' rules such as the Universal Law of Sustainability. Like me, the ecologist Tony Underwood has developed a popperian program of research; but here the logical technical term 'falsification' has been viewed from a distance as the word 'false'. This linguistic mistake has had drastic consequences; the discipline of ecology has been turned into a pseudoscience, a non-falsifiable science incapable of guiding the management of a commercial fishery. The absurdity that a traditional management should seek instruction from the environment in the form of 'facts' or data instead of subjecting bold tentative policies to a Darwinian-like selection by error elimination, results in a monism of 'scientific' ethics. That is: an ethics in which norms (values) are not chosen by the participants, but are viewed as scientifically achievable predictions.
Open Access
Demise of the garden of Acadia
(DVL Publishing Inc., Liverpool, Nova Scotia, 1981-07) Patriquin, David
In the late 1970s, plans were being developed for construction of a tidal power barrage at the mouth of the Annapolis River. Much of the land by the river in that area was dyked and was used by farmers for grazing and growing hay. Farmer Rob Warren had mole drained a portion of his dyked land at Belle Isle marsh to improve the drainage so that he could produce cereals and pulses for his dairy cattle. A consultants report had concluded that that the agricultural lands would not be impacted by the tidal power operation. The article outlines reasons why the mole drained land would be negatively impacted by the higher river levels and higher salinities associated with the tidal power operation.
Open Access
Water quality measurements on Williams Lake and Colpitt Lake (Halifax, N.S.) Dec 7-13, 2015 with reference to possible impacts of road salt
(Williams Lake Conservation Company, 2016-01-06) Patriquin, David
Concerns have been expressed by the Williams Lake Conservation Company (WLCC) about possible effects of renewed salting of roads close to Williams Lake on water quality of the lake. Such salting was replaced by sand and grit in the late 1980s which was maintained until January 2015 when regular salting was re-instigated. To provide some baseline data for assessment of future changes in the limnological conditions, observations of temperature, SPC (specific conductance, a measure of salt content), DO (dissolved oxygen) and pH were made at 4 sites on Williams Lake as well as at 5 inlets and the outlet in early December 2015 using a YSI Professional Plus meter & sensor provided by the Community Based Environmental Monitoring Network at St. Mary’s University. This also allowed for comparison with a set of similar observations made in 1990/91 by R. Scott during a period when use of road salt was restricted on nearby roads. Additional observations were made on Colpitt Lake. Some observations of SPC alone were made with a Hanna 9033 Conductivity meter and sensor. At a deep water site (~20 m) in Williams Lake sampled on Dec 7, 2015, there was an abrupt change between 7 and 9 meters depth, with very low DO in the hypolimnion (6-10% oxygen saturation at depths of 9-20 m, versus 96-98% at 7.2 m and shallower), and increased SPC at depths of 9-20 m (306-307 μS/cm) compared to values at depths of 7.2 m and shallower (278-281 μS/cm); the temperature was 5.5oC at all depths. In a healthy dimictic lake, the water has normally turned over by late fall and the deeper waters are well aerated which was the case on Nov 29, 1990. While the causes are not clear, the apparently delayed turnover and low oxygen in late 2015 raises concerns about the health of the lake and sensitivity to increased salt inputs. Comparisons of the SPC value at the outlet on Dec 8, 2015 and chloride values for 2 samples within the lake taken by the WLCC on Aug 3, 2015 with historical data are suggestive that (i) the “background” levels of salt loading have increased since 1990/91 even with restricted salt use, and (2) renewed salting in 2015 has further increased salt loading. Other observations illustrate the low salt content of water draining from undisturbed landscape (SPC values 34-59 μS/cm) which makes up about three-quarters of the watershed, and the significant salt loads in all streams draining developed landscapes (SPC values of 282-427 μS/cm where they enter the lakes). Governor’s Brook appears to be the single source of high salt water entering Colpitt Lake which has SPC values similar to those of Williams Lake. While the salt carried from developed areas is diluted by flows from the large blocks of undeveloped landscape in the Williams Lake watershed, it is clear that such dilution is not sufficient to lower salt to levels of no concern. Follow-up studies are suggested.
Open Access
What is a fish stock assessment? Is it a sound method? Can it be used to manage a commercial fishery?
(2015-09) Corkett, Christopher John
Under Karl Popper's non-inductive theory of method arguments are never carried from data to advice as in a fish stock assessment. That is: a distinction or 'demarcation' has to be made between (i) a Lamarckian-like inductive argument involving instruction from the environment and (ii) a Darwinian-like selection by falsification involving selection by the environment. The absurdity that we should seek to manage the marine environment by looking for instruction from the data, instead of using our own intellect in the form of bold imaginative policies, results in a monism of 'scientific' ethics.I conclude a fish stock assessment is an unsound method. Its data-based inductive arguments have no problem-solving capacity and are to be held responsible for the collapse of some of the World's largest Gadoid fisheries. A deductive method capable of problem-solving would involve the selection of bold policies by falsification, given as error elimination (EE) in Karl Popper's trial and error heuristic. An example of policy selection by falsification would be the use of lobster landings (LL) as a negative feedback index by the 120+ year old inshore Maritime lobster fishery.
Open Access
The sound management of a fishery as a social engineering: applying Karl Popper's demarcation criterion to an Area 2 stock of Pacific halibut
(2014-10-23) Corkett, Christopher
The Newfoundland fishery for Atlantic cod was once the largest cod fishery in the World. In the early 1990s this fishery formed part of an Atlantic Canadian groundfish fishery collapse that has become one of the World's most prominent case studies of failure in fisheries mangement. The proposition to be advanced in this paper is that this fishery collapse is attributable to the use of unsound inductive arguments that were over-reliant on 'facts' or data. Under Karl Popper's non-inductive theory of method the ability to understand and avoid a fishery collapse is not dependent on the certainty of the 'facts' or data, it is depedent on the soundness of the decisions that are taken. What is, or is not, a sound decision or sound argument is not a distinction discoverable 'naturalistically' by empirical science; rather, the distinction is based in logic. Sound management decisions require a critical or falsifiable view of science that has to be 'demarcated' from a verifiable and inductive view, two views illustrated in this paper by a singular 47 year data set of Pacific halibut. It is my prescriptive thesis that if the World's commercial fisheries are to realise a long-term sustainability they will need to be manged under a critical or falsifiable view of science in which a trial and error mangement is guided by rules of thumb with prior improbability. After all, Canada's inshore Maritime lobster fishery has been manged in this way for well over a century without collapse.
Open Access
Critical thinking through the eyes of Richard Paul and Karl Popper
(2014-10-08) Corkett, Chris
This 1993 workshop marks the beginning of my new logical or metaphysical research program on the application of Karl Popper’s non-inductive theory of method to the management of the World’s commercial fisheries. The view, according to which methodology is an empirical science in its turn – a study of the actual behaviour of scientists, or of the actual procedure of ‘science’ – may be described as ‘naturalistic’. Whereas in my first program of research on marine copepods (1963 to 1993) I learnt more and more about less and less, in my second anti-naturalistic application of Popper’s non-inductive method to the management of a commercial fishery (1993 to present) I am learning less and less about more and more.
Open Access
Ecological Assessment of the Plant Communities of the Williams Lake Backlands
(The Williams Lake Conservation Company, 2014-02-12) Hill, Nick; Patriquin, David
The Williams Lake Backlands (WLB), covering approximately 200 ha, are the larger, undeveloped part of the Williams Lake Watershed which includes Colpitt Lake and Williams Lake. The WLB are part of "Purcell's Cove Backlands" (approximately the 1350 ha) which include the land between Purcell's Cove Road and Herring Cove Road from Williams Lake at the northwest end to Powers Pond at the southeast end. Lying only two kilometers from peninsular Halifax, the WLB are near pristine wilderness. We traversed various routes through the WLB on twelve separate days between May 13 and Nov. 8, 2013 to document plant communities and wetlands for the Williams Lake Conservation Company, a volunteer organization concerned with stewardship of the Williams Lake watershed. The WLB present a mosaic of landscapes and plant communities associated with high variability on a fairly small scale in the topography, depth of soil/till, drainage and surface water storage and in the ages since disturbance of the associated plant communities. That variability in turn is related to the presence of glacially scoured hard granite outcrops of South Mountain Batholith, outcroppings of highly folded and metamorphosed Halifax Group black slates and siltstones of the Meguma Supergroup, a contact zone between the two rock types, and glacial till. Overall, the plant communities are those of nutrient-poor, acidic environments and of fire-, wind-, and pest-driven disturbance regimes within a moist temperate, coastal region. Exotic (non-native) species are found only close to roads and houses at the edge of the WLB. These are "old process" plant communities with a high degree of ecological integrity. The fire dependent/fire adapted nature of the vegetation and carbon dating of charcoal from a core in a Jack Pine fen indicate that fires in the WLB are part of a long-term fire regime that predates European settlement. Indeed, the whole of the Purcell's Cove Backlands is one of the most fire-susceptible landscapes in Nova Scotia, the droughty, windswept high barrens acting as matchsticks. One result is the presence of an old process, fire dependent Jack Pine/Broom Crowberry Barrens community that is nationally unique to Nova Scotia, globally rare and of high conservation significance. In the northeastern U.S., this community transitions to the fire-dependent Pitch Pine/Broom Crowberry community which is well recognized as of high conservation value. The largest single patch of Jack Pine/Broom Crowberry Barrens within the Purcell's Backlands occurs within the WLB, and overall, the Jack Pine/Broom Crowberry Barrens in the Purcell's Cove Backlands are amongst if not the best, representatives of this community in Nova Scotia. The water regime in the WLB has features of dryland systems, with intermittent stream courses probably accounting for a majority of the water flow. Critical components such as Mountain Holly washes, vernal pools and boulder fields are not currently protected under Nova Scotia wetland and stream course regulations but are vital to maintenance of the larger wetlands and water quality of both surface and groundwater in the area. The undisturbed nature of this wilderness area, its mosaic of habitats with wetlands, lakes, streams, forest and barrens, and its location by the coast in the most urbanized area of the province make the WLB and the larger Purcell's Cove Backlands significant habitat for both breeding and migratory birds. It is suggested that conserving the WLB and the larger Purcell's Cove Backlands as natural systems reduces fire risk to adjacent communities compared to allowing more intrusions into the backlands. Implementing strategies such as those promoted in the northeastern U.S. for living compatibly with firestructured pitch pine ecosystems would enhance both fire protection for neighbouring communities and conservation of biodiversity in our backlands.
Open Access
Distinguishing input controls from ouput controls in Atlantic Canada's fisheries: explaining the decline and collapse of Newfoundland's Atlantic cod stocks
(2013-03-14) Corkett, Christopher J.
The lobster and groundfish fisheries of Atlantic Canada have been managed in very different ways. The Atlantic lobster fishery has been managed by input controls in which regulations have been developed by a posteriori deductive argument to control the intensity of the gear used to catch lobsters. By contrast the Atlantic groundfish fisheries have been managed by output controls involving the a priori inductive arguments of stock assessment in which limits are put on the amount of groundfish coming out of a fishery. Karl Popper excludes induction from his theory of method since induction leads to logical inconsistencies such as a 'scientific' ethics (i.e. the notion that science can on its own tell us what should be done), a fisheries example of which is the use of reference points and harvest guidelines in an attempt to guide the normative use of data. It is mt thesis that the prejudicial nature of a fish stock assessment with its embedded monism of 'scientific' ethics is to be held responsible for the overfishing and collapse of Atlantic groundfish fisheries including Newfoundland's Atlantic cod stocks. If Atlantic Canada's groundfish fisheries are to be managed by sound and rational decisions, they will have to join the Atlantic lobster fishery as a well regulated institution capable of controlling the levels of effort used to catch fish.
Open Access
Biological husbandry and the "nitrogen problem"
(Biological Agriculture and Horticulture, 1986) Patriquin, David G.
Since 1978, the author has been conducting research into the theory and practice of biological husbandry in collaboration with a farmer who stopped using pesticides and mineral fertilizers in 1976. Eggs are exported from the farm. About 60% of feed is grown on the farm in a legume-cereal rotation (faba beans-oats-clover-winter wheat), and plant and animal residues are recycled. Annual weeds function as a self-seeding cover crop, protecting the soil, conserving nutrients and fixing carbon where and when cultivated crops are not present. Yields average about 25% lower than those on conventional farms, but the farm is more profitable because of lower input costs. A nitrogen budget suggests that inputs of nitrogen are sufficient to sustain cereal yields equivalent to those of conventional systems. However, much of the annual input of N to cereal fields, in manure, is not available in the short term. Various laboratory and field studies suggest that as fertility or the biological activity of soils increases, problems related to immobilization of N by straw, phytoxicity and annual weeds decline, and that less manure is required to augment the N supply by a given amount. While N might be identified as the "limiting factor" for cereal production, alleviation of N shortages is dependent on intensifying cycling, rather than on increasing N inputs. This intensification is achieved by augmenting natural rhythms on the farm through appropriate tillage techniques, and by ensuring an abundance and high activity of the catalysts of the N cycle, i.e. of all of the farm biota.
Open Access
Some notes on the Aristotelian origin of the distinction between a falsificationist's and verificationist's view of science: together with corrections to my earlier account
(2012-10-31) Corkett, Christopher J.
It has not always been realised that Karl Popper's analytic distinction between the logically stronger falsificationist's view of science and the logically weaker verificationist's and inductivist's view of science is a modification of Aristotle's distnction between the notions 'all' and 'some'. This document traces this distinction anew in a way that corrects my earlier (Corkett, 1997) account in which a semantic rather than a logical view was taken of this distinction. For example: when writing the 1997 paperI was not aware that the universal law "All swans are white' represented a universal categorical proposition 'All S is P' where 'S' represented the subject 'swan' and the 'P' represented the predicate 'white'. In this document I try to cover some of the main points of my 1997 paper in a way that clarifies their origin in the Law of Tripartite Entailment, a logical rule unknown to me fifteen years ago.

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