title: The Effect of Effort: An analysis of Killeen's (1994) Mathematical Principles of Reinforcement

authors: Bjarnesen, Rebecca Claire

subjects: Mathematical Principles of Reinforcement

abstract: Mathematical Principles of Reinforcement (MPR, Killeen, 1994) is a mathematical model comprising three main concepts; an animal’s arousal to behaviour based on its motivation for a particular reinforcer, time and energy constraints on responding, and coupling between a response class and reinforcer. This experiment tested the ability of MPR to predict response rates when the minimum force requirement and topography of response was changed. Increasing the minimum force requirement was expected to increase the value of δ, the parameter related to response constraint. Altering the topography of the response was expected to also alter the δ value, as different response forms were expected to take different lengths of time to perform. There were four conditions; low force key, low force door, high force key and high force door, and 6 hens responded under each of these conditions in an ascending geometric series of Fixed Ratio (FR) values. It was shown that hens responded at a faster rate and to higher FR values when responding on the key than on the door, and for both apparatus, the hens stopped responding at lower FR values when weights were added. Unexpectedly, there were no statistically significant differences in the value of δ across conditions, but the values for a, meant to represent the animals’ arousal, did change. It was suggested that the changes in a reflected changes in the animals’ motivation to perform the different responses, probably due to rewarding or aversive properties of the operant response related to the different response forms.

text: The Effect of Effort: An analysis of Killeen's (1994) Mathematical Principles of Reinforcement Mathematical Principles of Reinforcement (MPR, Killeen, 1994) is a mathematical model comprising three main concepts; an animal’s arousal to behaviour based on its motivation for a particular reinforcer, time and energy constraints on responding, and coupling between a response class and reinforcer. This experiment tested the ability of MPR to predict response rates when the minimum force requirement and topography of response was changed. Increasing the minimum force requirement was expected to increase the value of δ, the parameter related to response constraint. Altering the topography of the response was expected to also alter the δ value, as different response forms were expected to take different lengths of time to perform. There were four conditions; low force key, low force door, high force key and high force door, and 6 hens responded under each of these conditions in an ascending geometric series of Fixed Ratio (FR) values. It was shown that hens responded at a faster rate and to higher FR values when responding on the key than on the door, and for both apparatus, the hens stopped responding at lower FR values when weights were added. Unexpectedly, there were no statistically significant differences in the value of δ across conditions, but the values for a, meant to represent the animals’ arousal, did change. It was suggested that the changes in a reflected changes in the animals’ motivation to perform the different responses, probably due to rewarding or aversive properties of the operant response related to the different response forms.

year: 2011

title: Biology of mustelids: reviews and future directions

authors: Mcdonald, Robbie A.

subjects: Carnivora

abstract: The mustelidae is the largest and most diverse family of the Carnivora. The family is unified by an ancestral long-thin body plan, and the physical, physiological and ecological consequences this has for them. Yet within the family, even within species, life history patterns can be surprisingly variable. From the world’s smallest carnivore, the Weasel (Mustela nivalis), the family ranges almost a thousand-fold in weight to the Sea Otter (Enhydra lutris). Whereas Stoats (Mustela ermine)rank among the most numerous of carnivores and are common throughout the northern Holarctic, Black-footed Ferrets (M. nigripes)live at the brink of extinction, supported only by high-profile reintroductions.

text: Biology of mustelids: reviews and future directions The mustelidae is the largest and most diverse family of the Carnivora. The family is unified by an ancestral long-thin body plan, and the physical, physiological and ecological consequences this has for them. Yet within the family, even within species, life history patterns can be surprisingly variable. From the world’s smallest carnivore, the Weasel (Mustela nivalis), the family ranges almost a thousand-fold in weight to the Sea Otter (Enhydra lutris). Whereas Stoats (Mustela ermine)rank among the most numerous of carnivores and are common throughout the northern Holarctic, Black-footed Ferrets (M. nigripes)live at the brink of extinction, supported only by high-profile reintroductions.

year: 2000

title: Comparative fish abundance in the shallow Waikato lakes Whangape and Hakanoa

authors: Hicks, Brendan J.

abstract: The Waikato-Tainui College for Research and Development contracted the University of Waikato to conduct boat electrofishing estimates of the fish abundance in lakes Whangape and Hakanoa; both are shallow, riverine lakes in the lower Waikato River floodplain and are about 2,000 years old. Lake Whangape (latitude 37.46853°S, longitude 175.05120°W) is a large (1,450 ha), shallow (maximum depth 2.7 m) lake to the west of the Waikato River; Lake Hakanoa (latitude 37.55258°S, longitude 175.16859°W) is a 52-ha lake in suburban Huntly with a maximum depth of 2.5 m.
We fished 10 sites for 10 mins in both lakes Whangape and Lake Hakanoa; sites fished were 253-609 m long (1,012-2,436 m² in area) in Lake Whangape and 125-276 m long (500-1,104 m² in area) in Lake Hakanoa.
No submerged aquatic macrophytes were seen in either lake. Fishing was conducted close to the water's edge in Lake Hakanoa, but the shallow margins in Lake Whangape restricted fishing at most sites to 30-70 m from the shoreline. The shoreline was much more accessible in Lake Hakanoa, and was dominated by raupo (Typha orientalis) with willows (Salix spp.) in places. Submerged tree trunks and logs in Lake Hakanoa made navigation difficult in parts of the lake margins.
We caught a total of 118 fish in Lake Whangape, where shortfin eels (Anguilla australis) were the most abundant fish, and 594 fish in Lake Hakanoa, where gambusia (Gambusia affinis) the most abundant species. In Lake Whangape, shortfin eels comprised the greatest total biomass (12.4 kg), with koi carp (Cyprinus carpio) almost equally abundant (11.4 kg). In Lake Hakanoa, koi carp were most abundant (74.4 kg), followed by shortfin eels (22.1 kg).
Fish were unevenly spread among sites in Lake Whangape and koi carp were relatively sparsely among sites. In Lake Hakanoa, in contrast, fish were more evenly spread among sites, but with higher concentrations of catfish (Ameiurus nebulosus) and goldfish (Carassius auratus) at a few sites. Biomass of fish caught in each of the ten 10-min fishing shots reflected the numerical distributions, with some wide variations between sites. Fish densities were generally lower in Lake Whangape than in Lake Hakanoa; however, common smelt (Retropinna retropinna) and grey mullet (Mugil cephalus) occurred in Whangape but not in Hakanoa. Areal fish biomass was dominated by shortfin eels and koi carp in Lake Whangape, but koi carp dominated the fish biomass in Lake Hakanoa, despite the smaller number of carp than eels. This was because of the large mean weight of koi carp (about 1,000 g) compared to the smaller shortfin eels (mean weight about 200 g in both lakes).

text: Comparative fish abundance in the shallow Waikato lakes Whangape and Hakanoa The Waikato-Tainui College for Research and Development contracted the University of Waikato to conduct boat electrofishing estimates of the fish abundance in lakes Whangape and Hakanoa; both are shallow, riverine lakes in the lower Waikato River floodplain and are about 2,000 years old. Lake Whangape (latitude 37.46853°S, longitude 175.05120°W) is a large (1,450 ha), shallow (maximum depth 2.7 m) lake to the west of the Waikato River; Lake Hakanoa (latitude 37.55258°S, longitude 175.16859°W) is a 52-ha lake in suburban Huntly with a maximum depth of 2.5 m.
We fished 10 sites for 10 mins in both lakes Whangape and Lake Hakanoa; sites fished were 253-609 m long (1,012-2,436 m² in area) in Lake Whangape and 125-276 m long (500-1,104 m² in area) in Lake Hakanoa.
No submerged aquatic macrophytes were seen in either lake. Fishing was conducted close to the water's edge in Lake Hakanoa, but the shallow margins in Lake Whangape restricted fishing at most sites to 30-70 m from the shoreline. The shoreline was much more accessible in Lake Hakanoa, and was dominated by raupo (Typha orientalis) with willows (Salix spp.) in places. Submerged tree trunks and logs in Lake Hakanoa made navigation difficult in parts of the lake margins.
We caught a total of 118 fish in Lake Whangape, where shortfin eels (Anguilla australis) were the most abundant fish, and 594 fish in Lake Hakanoa, where gambusia (Gambusia affinis) the most abundant species. In Lake Whangape, shortfin eels comprised the greatest total biomass (12.4 kg), with koi carp (Cyprinus carpio) almost equally abundant (11.4 kg). In Lake Hakanoa, koi carp were most abundant (74.4 kg), followed by shortfin eels (22.1 kg).
Fish were unevenly spread among sites in Lake Whangape and koi carp were relatively sparsely among sites. In Lake Hakanoa, in contrast, fish were more evenly spread among sites, but with higher concentrations of catfish (Ameiurus nebulosus) and goldfish (Carassius auratus) at a few sites. Biomass of fish caught in each of the ten 10-min fishing shots reflected the numerical distributions, with some wide variations between sites. Fish densities were generally lower in Lake Whangape than in Lake Hakanoa; however, common smelt (Retropinna retropinna) and grey mullet (Mugil cephalus) occurred in Whangape but not in Hakanoa. Areal fish biomass was dominated by shortfin eels and koi carp in Lake Whangape, but koi carp dominated the fish biomass in Lake Hakanoa, despite the smaller number of carp than eels. This was because of the large mean weight of koi carp (about 1,000 g) compared to the smaller shortfin eels (mean weight about 200 g in both lakes).

year: 2016