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Evaluation of the comparative efficacy of fumigants and acute poison baits against Indian crested porcupine, Hystrix indica
Forest Ecology and Management, 48 (1992) 295-303 Elsevier Science Publishers B.V., Amsterdam
295
Evaluation of the comparative efficacy of fumigants and acute poison baits against Indian crested porcupine, Hystrix indica A.A. Khan a, M. Ahmad b, S. Ahmad ~and S.W.A. Rizvi~ aVertebratePest Control Laboratory, National AgriculturalResearch Centre, P.O.N. L H., Park Road, Islamabad, Pakistan bDepartment of Zoology, Universityof Karachi. Karachi-32. Pakistan !"ertebratePest Control Laboratory, Pest Management Research Institute. P.O. Box-8401, Universityof Karachi, Karachi-32, Pakistan (Accepted7 February 1991)
ABSTRACT Khan, A.A.,Ahmad, M., Ahmad,S. and Rizvi, S.W.A., 1992.Evaluationof the comparativeefficacy of fumigantsand acute poison baits against Indian crested porcupine, Hystrix indica. For. Ecol. Manage., 48: 295-303. Field trials were conductedto determine the efficacyof three fumigants and two acute poisons against the crested porcupine, Hystrix indica, in forest plantations and croplands. The highest mortality was obtained with the use of a two-ingredientgas cartridge, followedby sodium cyanide and aluminium phosphide. Strychninebaits were lesseffectivethan baits prepared fromsodiumfluoroacetate (1080). Further large-scaleoperational research studies are neededto developthe use of a twoingredient gas cartridgeas a singlemanagementtool againstH. indica and other burrowingporcupines.
INTRODUCTION Porcupines o f the genus H y s t r i x are among the largest Old World rodents and have been recognised as serious pests in forests and o f non-traditional crops in Pakistan and m a n y other countries. Although biology and control o f the New World genus E r e t h i z o n has been extensively studied (Curtis and Kozicky, 1944; Shapiro, 1949; Spencer, 1950; Faulkner and Dodge, 1962; Krefting et al., 1962; Van Deusen and Myers, 1962), H. indica Kerr, a species o f the genus H y s t r i x c o m m o n l y found in Pakistan, has been little studied no doubt because o f its nocturnal behaviour and specific habitat se!~ction~ According to Roberts ( i 9 7 7 ) , it is abundant all over the coun~T and can be found in s%~:~,:. mountain regions o f Baluchistan up to 2750 m elevation. Surveys con~!,~-~.d by a P a k i s t a n - F A O / U N D P project on vertebrate pest control have indicated that H. indica is widely distributed in irrigated forest plan-
© 1992 Elsevier ~cience Publishers B.V. All fights reserved 0378-1127/92/$05.00
296
A.A. KHAN ET AL.
tations and along link canals in Punjab and Sindh. The high, raised, dirt-built, embankments of the canals have provided a suitable habitat for the burrowing rodents which have helped in their spread in the croplands. Ahmad and Chaudhry (1977) studied the habits, habitat and control of H. indica in the forest plantations of central Pubjab. Greaves and Khan ( 1978 ) recorded one burrow per 5.7 ha in Changa Manga, and in Chichawatni one burrow per 14.5 ha. Earlier, Prater ( 1971 ) described the burrow structure of this species. Recently, Arshad (1987 ) and Arshad et al. (1988) carried out some preliminary studies on habitat pattern, feeding preference, reproductive biology and strategy for the control of H. indica in agricultural areas around Faisalabad. Damage and losses to crops such as potatoes, groundnuts and maize have been reported by Ahmad et al. ( 1987 ) and Brooks et al. (1988). Insignificant damage of 0.38% was found in 22 maize fields in the Faisalabad district, and damage was much less common in the groundnut fields in Attock, Rawalpindi and Chakwal districts. Porcupines also attack orchard trees, seedlings of mangoes, apricot and citrus, and sprouting sugar-cane seed. Alkon (1985) and Alkon and Saltz ( 1985 ) reported damage to irrigated potatoes fields in the Negev desert of southern Israel. The most important porcupine damage, however, occurs in forestry and reforestation areas (Chaudhry, 1970; Chaudhry and Ahmad, 1975 ). Melia azedarach (52.5%), Morus alba (24.3%) and Dalbergia sissoo (1.00%) are heavily damaged (Greaves and Khan, 1978). Taber et al. (1967) reported damage also to be common to M. alba in cropland areas of Punjab. Pine trees, Pinus longifolia, have been observed by the authors of this paper to be highly susceptible to porcupine damage in the upland valley of Kaghan in the North Western Frontier Province. Nawaz and Ahmad (1974) calculated a loss of 136136 ft 3 of wood in various Changa Manga plantations (5263 ha area). To date, the single account of pine damage by porcupines has been by Storm and Halvorson ( 1967 ), who studied the effect of injury by porcupines on radial growth of ponderosa pine, Pinus ponderosa, in Western Montana, USA. Preventive measures have been little studied, except for some preliminary work by Nawaz and Ahmad (1974), Chaudhry and Ahmad ( 1975 ) and Arshad et al. (1988). They used either aluminium phosphide (Phostoxin and Detia) or baits made from highly toxic insecticides, and obtained varying degrees of success. The efficacy of these materials has yet to be evaluated at the operational level. The results of the study reported in this paper are based on comparative trials of the efficacy of gases (hydrogen cyanide and a twoingredient pyrotechnic gas device) and baiting with acute poisons commonly used for porcupines in other countries. MATERIALS AND METHODS
The trials near Quetta (Baluchistan) were carded out from May to November 1981, and those in the Changa Manga forest plantations (Punjab)
297
EFFICACYOF PORCUPINECONTROL METHODS
rerrltor~ \
/
t
NI 24" . . . .
~
Fig. 1. Map of Pakistan showin ;experimentalsites. were from August to September 1983. The site locations are as shown in Fig. I. In these trials five chemical compounds were tested. For baiting purposes sodium fluoroacetate (90%) and strychnine (100%) were used, and for fumigation sodium cyanide (40% powder), aluminium phosphide and carbon monoxide generated from a two-ingredient cartridge were applied. The cartridge was made up ( w / w ) from sodium nitrate (65%) and ground charcoal (35%). The methods adopted for baiting and fumigation were as follows.
Baiting Baiting trials using sodium fluoroacetate (1080) were carried out near Sariab and Lora Pashin along a drainage canal and in dried up kareezes (underground water channels), where active porcupine burrows were located. From these places the porcupines visited the Government Vegetable Seed Production Farms and were causing serious damage to vegetables. Potatoes and squash were used as bait, and the poison was smeared on sliced potatoes and cut pieces of squash. Twenty burrows each in kareezes and along the drainage canal were treated with potato and squash baits. For each burrow treatment 2-4 pieces of baits (50-100 g) were placed 30 cm inside the burrow. Each active burrow was treated with 100-150 mg of 1080. These same methods were used also for strychnine baiting in Changa Manga plantations, where 60-80 mg of strychnine was used for each burrow. Post-treatment observations were made 48 h after baiting.
298
A.A. KHAN ET AL.
Fumigation The quantities used of the three fumigants are shown in Table 1. Sodium cyanide powder was pumped into active burrows using a 'Dust-R' pump (B&G Equipment Company, Plumsteadville, PA, USA). The procedure adopted was to seal off the emergency exist to the burrow and plug the mouth of one or two of the major active openings with brushwood. Before doing this, plastic hose-pipe measuring 1.5 m in length and 1.25 em in diameter was inserted deep into the burrow and then covered up firmly with soil, leaving about 25 cm of hose-pipe outside the burrow. After fumigation the hose-pipe was withdrawn from the burrow and blocked. For aluminium phosphide, Phostoxin tablets (each 3 g) were placed deep inside the burrow with the help of a shovel and the burrows were plugged with brushwood and dirt. For carbon monoxide, a two-ingredient cartridge was placed, after ignition, 25 cm deep into the burrow and, after making sure that smoke was being generated smoothly, the burrows were plugged. Post-treatment observations were taken 48 h after treatment. RESULTSAND DISCUSSION The results of the fumigation treatments are summarized in Table 1. Analysis of variance of the treatments indicated that there was no significant difference between the two locations ( F = 1.76, P > 0.05). The two-ingredient gas cartridge was the most effective of the three fumigants, giving complete mortality in four of the seven trials. The 200 g cartridge was as effective as the larger cartridge (250 g). The smaller cartridges ( 100 and 150 g) were less effective. Charcoal and sodium nitrate are relatively innocuous agents and have a low toxicity profile. However, the ignition product, carbon monoxide, is highly toxic to mammals. Savarie et al. (1980) stated that its inhalation toxicity is high and a concentration of 0.5% in air can cause collapse, unconsciousness, and death within minutes. However, with the use of carbon monoxide generating cartridge in porcupine burrows there would be minimal, if any, adverse effects on the environment because the gas is inactivated by the soil. Aluminium phosphide treatment proved to be less effective than the carbon monoxide gas. Because various dose levels were used (2-6 tablets per burrow), the reduction in activity ranged between 43 and 87%. The highest kill (87%) was obtained with six tablets per burrow (range 36-87%). The efficacy at four tablets per burrow varied at the two locations 43% at (Lora Pashin and 87% at Changa Manga). The lower level at Lora Pashin was the result of cracked and dry soil along the drainage canal, which could not hold a sufficient quantity of phosphine gas inside the burrow to kill the porcupines. The soil in Changa Manga plantations was compact loam, which helped to retain sufficient gas inside the burrow to kill the porcupines. Aluminium
Location
Lora Pashin, Queua Sariab, Quetta Changa Manga Changa Manga Changa Manga Changa Manga Sariab, Quetta Lora Pashin, Quetta Lora Pashin, Quetta Changa Manga Changa Manga Changa Manga Changa Manga Changa Manga
Site no.
i 2 3 4 5 6 7 8 9 l0 Il 12 !3 14
Aluminium phosphide Ahminium phosphide Ahminium phosphide Aluminium phosphide Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Sodium cyanide Sodium cyanide Sodium cyanide
Fumigant
4 tablets (3 g each) 6 4 2 100 g 150 g 200 g 200 g 250 g 250 g 250 g 15 strokes (9.45 g) 25 strokes ( 15.75 g) 35 strokes (22.05 g)
Quantity of fumigant per burrow
Results of the efficacy of fumigant treatments against H. indica
TABLE I
7 6 8 10 25 3i 8 l0 7 27 18 23 17 25
No. of burrows treated
No. of burrows remaining closed
No. of reopened burrows 43 83 87 50 72 87 160 100 100 93 100 70 88 1110
% Reduction in activity
Location
Sariab, Quetta Sariab, Quetta Lora Pashin, Quetta Changa Manga Changa Manga Changa Manga
Site no.
1 2 3 4 5 6 Sodium fluoroacetate Sodium fluoroacetate Sodium fluoroacetate Sodium fluoroacetate Strychnine hydrochloride Strychnine hydrochloride
Treatment
Results of the efficacy ofbaiting treatments against H. indica
TABLE 2
Squash Squash Potatoes Potatoes Potatoes Squash
Bait material 18 6 24 36 I0 13
No. of burrows treated Bait taken from burrows
No. of active burrows after 48 h
67 100 92 92 60 20
% Reduction in activity
EFFICACY OF PORCUPINE CONTROL METHODS
301
phosphide has been used in the past against porcupines in forest plantations. Nawaz and Ahmad (1974) obtained an 80% kill in Changa Manga with two applications but did not report the dose applied. Chaudhry and Abroad ( 1975 ) used aluminium phosphide tablets at rates of 2-15 per burrow and obtained 100% mortality with 5, l0 and 15 tablets per burrow. They found that aluminium phosphide was more effective in loamy than in stony and sandy soils. Sodium cyanide used at three dose levels (9, 16 and 22 g per burrow) gave better results than were obtained with aluminium phosphide. A 100% reduction in activity was obtained at the 22 g level. This level of mortality was not achieved by Chaudhry and Ahmad (1975), who used this compound at a rate of I 12-400 g in plastic bags emptied in each burrow, and obtained only a 50% kill at 400 g, the highest dose per burrow. By this method, hydrogen cyanide gas is not produced in sufficient quantity; also, it is not evenly distributed through the burrow. By the method employed in this study the sodium cyanide powder is evenly distributed through the burrow and reacts quickly with the moist air inside to produce a sufficient quantity of hydrogen cyanide gas to kill the porcupines. The results of baiting treatments with sodium fluoroacetate and strychnine are summarized in Table 2. Analysis of variance of the treatments indicated a significant difference between 1080 and strychnine baiting (F=8.58, P<0.05). Baiting with 1080 was highly effective and caused an average of 88% reduction in animal activity (range 67-100%). Strychnine was less effective and reduced animal activity by 400/0 (range 20-40%). Similarly, Nawaz and Abroad (1974) found strychnine baiting to be ineffective against porcupines. However, these workers did not provide any efficacy data. There was no difference (P> 0.05) between potato and squash bait when used with 1080. Some workers have evaluated the use of unconventional pesticides against porcupines. Chaudhry and Ahmad (1975) tried fruit and vegetable baits of potassium cyanide, zinc phosphide, coumatetralyl and sevin. Mortality of 100% was obtained with potassium cyanide apple bait, whereas baits of other compounds were either avoided or were not eaten by the animals. The authors did not describe the doses applied for each compound. Arshad et al. (1988) evaluated the efficacy of various kinds of baits (gourd, chopped mango stones, boiled maize ) prepared from temik 10G, Warfarin (100%), 1080 and endrin (19.5%) and obtained 100% and 86% kill with 1080 and temik respectively, and varying degrees of success (0-50%) with the other poisonous baits. With the use of the highly toxic material prepared from 1080, temik, endrin and strychnine, there may be some adverse effects on non-target animal species such as jackals, foxes and rabbits, which may eat the leftover bait when occupying the empty burrow. However, there would be minimal or zero el-
302
A.A.KHANETAL.
fects w i t h t h e use o f t h e v a r i o u s f u m i g a n t s e v a l u a t e d in this study. N o a d v e r s e effects o n n o n - t a r g e t s p e c i e s were n o t e d d u r i n g t h e s e trials. ACKNOWLEDGEMENTS T h e a u t h o r s a r e t h a n k f u l t o J o e E. B r o o k s for r e v i e w i n g t h e m a n u s c r i p t a n d his c o m m e n t s a n d N a s i r A l a m for d a t a analysis.
REFERENCES Ahmad, A. and Chaudhry, M.I., 1977. Studies on habits, habitat and damage of porcupines, Hystrix indiea, Rodentia: Mammalia. Pak. J. For., 27 (3): 147-150. Ahmad, E., Hussain, I., Khan, M.H. and Brooks, J.E., 1987. Vertebrate pest damage to maize in Faisalabad district, Pakistan. Tech. Rep. 10, GOP/USAID Project on Vertebrate Pest Control, NARC, Islamabad, 6 pp. Alkon, P.U., 1985. Patterns of crested porcupine (Hystrix indica) damage to cultivated potatoes. Agric. Ecosystems Environ., 14: 171-183. AIkon, P.U. and Saltz, D., 1985. Potatoes and the nutritional ecology of crested porcupines in desert biome. J. Appl. Ecol., 22: 727-737. Arshad, M.I., 1987. Studies on habitat pattern, feeding preferences, reproductive biology and strategy for control of Indian crested porcupine (Hystrix indica Linn. ) around Faisalabad agriculture biomes. M.Sc. Thesis, University of Agriculture, Faisalabad, 77 pp. Arshad, M.I., Khan, R.A. and Khaliq, A., 1988. Strategies for the control of Indian crested porcupine, Hystrix indica. Pak. J. Sci. Ind. Res., 31 ( 1): 784-785. Brooks, J.E., Ahmad, E. and Hussain, I., 1988. Characteristics of,:lamage by vertebrate pests to groundnut in Pakistan. Proc. 13th Vert. Pest Conf., University of California, Davis, pp. 129133. Chaudhry, G.U., 1970. Wildlife - an economic zoologist's view point. Pak. J. For., 20: 369372. Chaudhry, M.I. and Ahmad, A., 1975. Trials of poisonous gases and baits against porcupines. Pak. J. For., 25: 46-50. Curtis, J.D. and Kozicky, E.E., 1944. Observations on the eastern porcupine. J. Mammal., 25: 137-146. Faulkner, C.E. and Dodge, W.E., 1962. Control of the porcupine in New England. J. For., 60: 36-37. Greaves, J.H. and Khan, A.A., 1978. The status and control of porcupines, genus Hystrix as forest pests. Commonw. For. Rev., 57( 1 ): 25-31. Krefting, L.W., Stoecheler, J.H., Bradle, B.J. and Fitzwater, W.D., 1962. Porcupine - relationship in the Lake States. J. For., 60: 325-333. Nawaz, A. and Ahmad, F., 1974. Control of porcupines in Changa Manga irrigated plantation. Tech. Rep. Forest Departmept, Pubjab, 16 pp. Prater, S.H., 1971. The Book of Indian Animals 3rd edn. Bombay Natural History Society, 324 PP. Roberts, TJ., 1977. The Mammals of Pakistan. Ernest Benn, London, 361 pp. Savane, P.J., Tinger, J.R., Elias, D.J. and Hayes, D.J., 1980. Development of a simple twoingredient pyrotechnic fumigant. In: J.P. Clark (Editor), Proc. 9th Vcrt. Pest Conf., Fresno, CA, pp. 215-221.
EFFICACYOFPORCUPINECONTROLMETHOD~
303
Shapiro, J., 1949. Ecological and life history no~es on the porcupine in the Adirondacks. J. Mammal., 30: 247-257. Spencer, D.A., 1950. The porcupine: its economic status and control. US Fish Wildl. Serv. Wildl. Leaflet 328, 7 pp. Storm, G.L. and Halvorson, C.H., 1967. Effect of injury by porcupines on radial growth of Ponderosa pine. J. For., October:. 740-743. Taber, R.D., Shed, A.N. and Ahmad, M.S., 1967. Mammals of the Lyallpur Region, West Pakistan. J. Mammal., 48: 392-407. Van Deusen, J.L. and Myers, C.A., 1962. Porcupine damage in immature stands of Ponder,Tsa pine in the Black Hills. J. For., 60:81 I-813.
295
Evaluation of the comparative efficacy of fumigants and acute poison baits against Indian crested porcupine, Hystrix indica A.A. Khan a, M. Ahmad b, S. Ahmad ~and S.W.A. Rizvi~ aVertebratePest Control Laboratory, National AgriculturalResearch Centre, P.O.N. L H., Park Road, Islamabad, Pakistan bDepartment of Zoology, Universityof Karachi. Karachi-32. Pakistan !"ertebratePest Control Laboratory, Pest Management Research Institute. P.O. Box-8401, Universityof Karachi, Karachi-32, Pakistan (Accepted7 February 1991)
ABSTRACT Khan, A.A.,Ahmad, M., Ahmad,S. and Rizvi, S.W.A., 1992.Evaluationof the comparativeefficacy of fumigantsand acute poison baits against Indian crested porcupine, Hystrix indica. For. Ecol. Manage., 48: 295-303. Field trials were conductedto determine the efficacyof three fumigants and two acute poisons against the crested porcupine, Hystrix indica, in forest plantations and croplands. The highest mortality was obtained with the use of a two-ingredientgas cartridge, followedby sodium cyanide and aluminium phosphide. Strychninebaits were lesseffectivethan baits prepared fromsodiumfluoroacetate (1080). Further large-scaleoperational research studies are neededto developthe use of a twoingredient gas cartridgeas a singlemanagementtool againstH. indica and other burrowingporcupines.
INTRODUCTION Porcupines o f the genus H y s t r i x are among the largest Old World rodents and have been recognised as serious pests in forests and o f non-traditional crops in Pakistan and m a n y other countries. Although biology and control o f the New World genus E r e t h i z o n has been extensively studied (Curtis and Kozicky, 1944; Shapiro, 1949; Spencer, 1950; Faulkner and Dodge, 1962; Krefting et al., 1962; Van Deusen and Myers, 1962), H. indica Kerr, a species o f the genus H y s t r i x c o m m o n l y found in Pakistan, has been little studied no doubt because o f its nocturnal behaviour and specific habitat se!~ction~ According to Roberts ( i 9 7 7 ) , it is abundant all over the coun~T and can be found in s%~:~,:. mountain regions o f Baluchistan up to 2750 m elevation. Surveys con~!,~-~.d by a P a k i s t a n - F A O / U N D P project on vertebrate pest control have indicated that H. indica is widely distributed in irrigated forest plan-
© 1992 Elsevier ~cience Publishers B.V. All fights reserved 0378-1127/92/$05.00
296
A.A. KHAN ET AL.
tations and along link canals in Punjab and Sindh. The high, raised, dirt-built, embankments of the canals have provided a suitable habitat for the burrowing rodents which have helped in their spread in the croplands. Ahmad and Chaudhry (1977) studied the habits, habitat and control of H. indica in the forest plantations of central Pubjab. Greaves and Khan ( 1978 ) recorded one burrow per 5.7 ha in Changa Manga, and in Chichawatni one burrow per 14.5 ha. Earlier, Prater ( 1971 ) described the burrow structure of this species. Recently, Arshad (1987 ) and Arshad et al. (1988) carried out some preliminary studies on habitat pattern, feeding preference, reproductive biology and strategy for the control of H. indica in agricultural areas around Faisalabad. Damage and losses to crops such as potatoes, groundnuts and maize have been reported by Ahmad et al. ( 1987 ) and Brooks et al. (1988). Insignificant damage of 0.38% was found in 22 maize fields in the Faisalabad district, and damage was much less common in the groundnut fields in Attock, Rawalpindi and Chakwal districts. Porcupines also attack orchard trees, seedlings of mangoes, apricot and citrus, and sprouting sugar-cane seed. Alkon (1985) and Alkon and Saltz ( 1985 ) reported damage to irrigated potatoes fields in the Negev desert of southern Israel. The most important porcupine damage, however, occurs in forestry and reforestation areas (Chaudhry, 1970; Chaudhry and Ahmad, 1975 ). Melia azedarach (52.5%), Morus alba (24.3%) and Dalbergia sissoo (1.00%) are heavily damaged (Greaves and Khan, 1978). Taber et al. (1967) reported damage also to be common to M. alba in cropland areas of Punjab. Pine trees, Pinus longifolia, have been observed by the authors of this paper to be highly susceptible to porcupine damage in the upland valley of Kaghan in the North Western Frontier Province. Nawaz and Ahmad (1974) calculated a loss of 136136 ft 3 of wood in various Changa Manga plantations (5263 ha area). To date, the single account of pine damage by porcupines has been by Storm and Halvorson ( 1967 ), who studied the effect of injury by porcupines on radial growth of ponderosa pine, Pinus ponderosa, in Western Montana, USA. Preventive measures have been little studied, except for some preliminary work by Nawaz and Ahmad (1974), Chaudhry and Ahmad ( 1975 ) and Arshad et al. (1988). They used either aluminium phosphide (Phostoxin and Detia) or baits made from highly toxic insecticides, and obtained varying degrees of success. The efficacy of these materials has yet to be evaluated at the operational level. The results of the study reported in this paper are based on comparative trials of the efficacy of gases (hydrogen cyanide and a twoingredient pyrotechnic gas device) and baiting with acute poisons commonly used for porcupines in other countries. MATERIALS AND METHODS
The trials near Quetta (Baluchistan) were carded out from May to November 1981, and those in the Changa Manga forest plantations (Punjab)
297
EFFICACYOF PORCUPINECONTROL METHODS
rerrltor~ \
/
t
NI 24" . . . .
~
Fig. 1. Map of Pakistan showin ;experimentalsites. were from August to September 1983. The site locations are as shown in Fig. I. In these trials five chemical compounds were tested. For baiting purposes sodium fluoroacetate (90%) and strychnine (100%) were used, and for fumigation sodium cyanide (40% powder), aluminium phosphide and carbon monoxide generated from a two-ingredient cartridge were applied. The cartridge was made up ( w / w ) from sodium nitrate (65%) and ground charcoal (35%). The methods adopted for baiting and fumigation were as follows.
Baiting Baiting trials using sodium fluoroacetate (1080) were carried out near Sariab and Lora Pashin along a drainage canal and in dried up kareezes (underground water channels), where active porcupine burrows were located. From these places the porcupines visited the Government Vegetable Seed Production Farms and were causing serious damage to vegetables. Potatoes and squash were used as bait, and the poison was smeared on sliced potatoes and cut pieces of squash. Twenty burrows each in kareezes and along the drainage canal were treated with potato and squash baits. For each burrow treatment 2-4 pieces of baits (50-100 g) were placed 30 cm inside the burrow. Each active burrow was treated with 100-150 mg of 1080. These same methods were used also for strychnine baiting in Changa Manga plantations, where 60-80 mg of strychnine was used for each burrow. Post-treatment observations were made 48 h after baiting.
298
A.A. KHAN ET AL.
Fumigation The quantities used of the three fumigants are shown in Table 1. Sodium cyanide powder was pumped into active burrows using a 'Dust-R' pump (B&G Equipment Company, Plumsteadville, PA, USA). The procedure adopted was to seal off the emergency exist to the burrow and plug the mouth of one or two of the major active openings with brushwood. Before doing this, plastic hose-pipe measuring 1.5 m in length and 1.25 em in diameter was inserted deep into the burrow and then covered up firmly with soil, leaving about 25 cm of hose-pipe outside the burrow. After fumigation the hose-pipe was withdrawn from the burrow and blocked. For aluminium phosphide, Phostoxin tablets (each 3 g) were placed deep inside the burrow with the help of a shovel and the burrows were plugged with brushwood and dirt. For carbon monoxide, a two-ingredient cartridge was placed, after ignition, 25 cm deep into the burrow and, after making sure that smoke was being generated smoothly, the burrows were plugged. Post-treatment observations were taken 48 h after treatment. RESULTSAND DISCUSSION The results of the fumigation treatments are summarized in Table 1. Analysis of variance of the treatments indicated that there was no significant difference between the two locations ( F = 1.76, P > 0.05). The two-ingredient gas cartridge was the most effective of the three fumigants, giving complete mortality in four of the seven trials. The 200 g cartridge was as effective as the larger cartridge (250 g). The smaller cartridges ( 100 and 150 g) were less effective. Charcoal and sodium nitrate are relatively innocuous agents and have a low toxicity profile. However, the ignition product, carbon monoxide, is highly toxic to mammals. Savarie et al. (1980) stated that its inhalation toxicity is high and a concentration of 0.5% in air can cause collapse, unconsciousness, and death within minutes. However, with the use of carbon monoxide generating cartridge in porcupine burrows there would be minimal, if any, adverse effects on the environment because the gas is inactivated by the soil. Aluminium phosphide treatment proved to be less effective than the carbon monoxide gas. Because various dose levels were used (2-6 tablets per burrow), the reduction in activity ranged between 43 and 87%. The highest kill (87%) was obtained with six tablets per burrow (range 36-87%). The efficacy at four tablets per burrow varied at the two locations 43% at (Lora Pashin and 87% at Changa Manga). The lower level at Lora Pashin was the result of cracked and dry soil along the drainage canal, which could not hold a sufficient quantity of phosphine gas inside the burrow to kill the porcupines. The soil in Changa Manga plantations was compact loam, which helped to retain sufficient gas inside the burrow to kill the porcupines. Aluminium
Location
Lora Pashin, Queua Sariab, Quetta Changa Manga Changa Manga Changa Manga Changa Manga Sariab, Quetta Lora Pashin, Quetta Lora Pashin, Quetta Changa Manga Changa Manga Changa Manga Changa Manga Changa Manga
Site no.
i 2 3 4 5 6 7 8 9 l0 Il 12 !3 14
Aluminium phosphide Ahminium phosphide Ahminium phosphide Aluminium phosphide Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Two-ingredient cartridge Sodium cyanide Sodium cyanide Sodium cyanide
Fumigant
4 tablets (3 g each) 6 4 2 100 g 150 g 200 g 200 g 250 g 250 g 250 g 15 strokes (9.45 g) 25 strokes ( 15.75 g) 35 strokes (22.05 g)
Quantity of fumigant per burrow
Results of the efficacy of fumigant treatments against H. indica
TABLE I
7 6 8 10 25 3i 8 l0 7 27 18 23 17 25
No. of burrows treated
No. of burrows remaining closed
No. of reopened burrows 43 83 87 50 72 87 160 100 100 93 100 70 88 1110
% Reduction in activity
Location
Sariab, Quetta Sariab, Quetta Lora Pashin, Quetta Changa Manga Changa Manga Changa Manga
Site no.
1 2 3 4 5 6 Sodium fluoroacetate Sodium fluoroacetate Sodium fluoroacetate Sodium fluoroacetate Strychnine hydrochloride Strychnine hydrochloride
Treatment
Results of the efficacy ofbaiting treatments against H. indica
TABLE 2
Squash Squash Potatoes Potatoes Potatoes Squash
Bait material 18 6 24 36 I0 13
No. of burrows treated Bait taken from burrows
No. of active burrows after 48 h
67 100 92 92 60 20
% Reduction in activity
EFFICACY OF PORCUPINE CONTROL METHODS
301
phosphide has been used in the past against porcupines in forest plantations. Nawaz and Ahmad (1974) obtained an 80% kill in Changa Manga with two applications but did not report the dose applied. Chaudhry and Abroad ( 1975 ) used aluminium phosphide tablets at rates of 2-15 per burrow and obtained 100% mortality with 5, l0 and 15 tablets per burrow. They found that aluminium phosphide was more effective in loamy than in stony and sandy soils. Sodium cyanide used at three dose levels (9, 16 and 22 g per burrow) gave better results than were obtained with aluminium phosphide. A 100% reduction in activity was obtained at the 22 g level. This level of mortality was not achieved by Chaudhry and Ahmad (1975), who used this compound at a rate of I 12-400 g in plastic bags emptied in each burrow, and obtained only a 50% kill at 400 g, the highest dose per burrow. By this method, hydrogen cyanide gas is not produced in sufficient quantity; also, it is not evenly distributed through the burrow. By the method employed in this study the sodium cyanide powder is evenly distributed through the burrow and reacts quickly with the moist air inside to produce a sufficient quantity of hydrogen cyanide gas to kill the porcupines. The results of baiting treatments with sodium fluoroacetate and strychnine are summarized in Table 2. Analysis of variance of the treatments indicated a significant difference between 1080 and strychnine baiting (F=8.58, P<0.05). Baiting with 1080 was highly effective and caused an average of 88% reduction in animal activity (range 67-100%). Strychnine was less effective and reduced animal activity by 400/0 (range 20-40%). Similarly, Nawaz and Abroad (1974) found strychnine baiting to be ineffective against porcupines. However, these workers did not provide any efficacy data. There was no difference (P> 0.05) between potato and squash bait when used with 1080. Some workers have evaluated the use of unconventional pesticides against porcupines. Chaudhry and Ahmad (1975) tried fruit and vegetable baits of potassium cyanide, zinc phosphide, coumatetralyl and sevin. Mortality of 100% was obtained with potassium cyanide apple bait, whereas baits of other compounds were either avoided or were not eaten by the animals. The authors did not describe the doses applied for each compound. Arshad et al. (1988) evaluated the efficacy of various kinds of baits (gourd, chopped mango stones, boiled maize ) prepared from temik 10G, Warfarin (100%), 1080 and endrin (19.5%) and obtained 100% and 86% kill with 1080 and temik respectively, and varying degrees of success (0-50%) with the other poisonous baits. With the use of the highly toxic material prepared from 1080, temik, endrin and strychnine, there may be some adverse effects on non-target animal species such as jackals, foxes and rabbits, which may eat the leftover bait when occupying the empty burrow. However, there would be minimal or zero el-
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fects w i t h t h e use o f t h e v a r i o u s f u m i g a n t s e v a l u a t e d in this study. N o a d v e r s e effects o n n o n - t a r g e t s p e c i e s were n o t e d d u r i n g t h e s e trials. ACKNOWLEDGEMENTS T h e a u t h o r s a r e t h a n k f u l t o J o e E. B r o o k s for r e v i e w i n g t h e m a n u s c r i p t a n d his c o m m e n t s a n d N a s i r A l a m for d a t a analysis.
REFERENCES Ahmad, A. and Chaudhry, M.I., 1977. Studies on habits, habitat and damage of porcupines, Hystrix indiea, Rodentia: Mammalia. Pak. J. For., 27 (3): 147-150. Ahmad, E., Hussain, I., Khan, M.H. and Brooks, J.E., 1987. Vertebrate pest damage to maize in Faisalabad district, Pakistan. Tech. Rep. 10, GOP/USAID Project on Vertebrate Pest Control, NARC, Islamabad, 6 pp. Alkon, P.U., 1985. Patterns of crested porcupine (Hystrix indica) damage to cultivated potatoes. Agric. Ecosystems Environ., 14: 171-183. AIkon, P.U. and Saltz, D., 1985. Potatoes and the nutritional ecology of crested porcupines in desert biome. J. Appl. Ecol., 22: 727-737. Arshad, M.I., 1987. Studies on habitat pattern, feeding preferences, reproductive biology and strategy for control of Indian crested porcupine (Hystrix indica Linn. ) around Faisalabad agriculture biomes. M.Sc. Thesis, University of Agriculture, Faisalabad, 77 pp. Arshad, M.I., Khan, R.A. and Khaliq, A., 1988. Strategies for the control of Indian crested porcupine, Hystrix indica. Pak. J. Sci. Ind. Res., 31 ( 1): 784-785. Brooks, J.E., Ahmad, E. and Hussain, I., 1988. Characteristics of,:lamage by vertebrate pests to groundnut in Pakistan. Proc. 13th Vert. Pest Conf., University of California, Davis, pp. 129133. Chaudhry, G.U., 1970. Wildlife - an economic zoologist's view point. Pak. J. For., 20: 369372. Chaudhry, M.I. and Ahmad, A., 1975. Trials of poisonous gases and baits against porcupines. Pak. J. For., 25: 46-50. Curtis, J.D. and Kozicky, E.E., 1944. Observations on the eastern porcupine. J. Mammal., 25: 137-146. Faulkner, C.E. and Dodge, W.E., 1962. Control of the porcupine in New England. J. For., 60: 36-37. Greaves, J.H. and Khan, A.A., 1978. The status and control of porcupines, genus Hystrix as forest pests. Commonw. For. Rev., 57( 1 ): 25-31. Krefting, L.W., Stoecheler, J.H., Bradle, B.J. and Fitzwater, W.D., 1962. Porcupine - relationship in the Lake States. J. For., 60: 325-333. Nawaz, A. and Ahmad, F., 1974. Control of porcupines in Changa Manga irrigated plantation. Tech. Rep. Forest Departmept, Pubjab, 16 pp. Prater, S.H., 1971. The Book of Indian Animals 3rd edn. Bombay Natural History Society, 324 PP. Roberts, TJ., 1977. The Mammals of Pakistan. Ernest Benn, London, 361 pp. Savane, P.J., Tinger, J.R., Elias, D.J. and Hayes, D.J., 1980. Development of a simple twoingredient pyrotechnic fumigant. In: J.P. Clark (Editor), Proc. 9th Vcrt. Pest Conf., Fresno, CA, pp. 215-221.
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Shapiro, J., 1949. Ecological and life history no~es on the porcupine in the Adirondacks. J. Mammal., 30: 247-257. Spencer, D.A., 1950. The porcupine: its economic status and control. US Fish Wildl. Serv. Wildl. Leaflet 328, 7 pp. Storm, G.L. and Halvorson, C.H., 1967. Effect of injury by porcupines on radial growth of Ponderosa pine. J. For., October:. 740-743. Taber, R.D., Shed, A.N. and Ahmad, M.S., 1967. Mammals of the Lyallpur Region, West Pakistan. J. Mammal., 48: 392-407. Van Deusen, J.L. and Myers, C.A., 1962. Porcupine damage in immature stands of Ponder,Tsa pine in the Black Hills. J. For., 60:81 I-813.