The Affect of Invasive Plant Species on Birds


Invasive plant species have an impact in the diversity of bird species in the ecosystem. The study involved examining the habitat of the bird species in Wattle Park in order to determine the effect of invasive plant species introduced intentionally or unintentionally in the park. Major of the invasive plant species in the park is destructive and affect the habitat of the fauna. Conserving the habitat in Wattle Park is essential since this is a tourist attraction scene that need frequent evaluation of the presence of destructive invasive species. Trees, shrubs and birds were the main targets of the study. Observation, counting the number of birds, and identifying the taxa of the birds were the standard methodologies used in the study. Eight bird species inhabited the trees and shrubs. The results indicated that birds’ preferred to inhabit trees to shrubs.

Aim of the study

Environmental conservation forms part of a global concern and investigation, especially on wildlife habitat. People visit the national park and conserved reserves for research and recreation purpose (Grice 2006). Wattle Park has a bird sanctuary that attracts visitors that are fun of birds watching and other recreational purposes. What is the preferred habitat of birds in the Wattle Park?

Study methodology

The experiment involved counting the bird species in four sites. Two sites involved counting birds on trees and the other two sites involved counting birds on shrubs. The bird species counted were a magpie, crow, rainbow parrot, rosella parrot, noisy miner, species number 1, green parrot, and raven. The results of the experiment are as shown in Table 1.

Location type Tree Tree Tree Tree Tree Tree Shrubs Shrubs Shrubs Shrubs Shrubs Shrubs
Sites Site 1 Site 2 Site 3 Site 4
Experiment number 1 2 3 1 2 3 1 2 3 1 2 3
Birds type
Magpie 7 5 9 1 3 0 1 3 5 2 4 3
Crow 3 2 0 11 4 9 4 3 4 2 5 2
Rainbow Parrot 2 8 4 3 0 0 2 5 4 0 6 4
Rosella parrot 1 3 2 2 3 0 1 0 2 0 2 3
Noisy miner 21 13 9 24 14 6 8 3 6 5 13 18
Species number 1 1 0 5 0 2 0 0 1 0 0 0 0
Green parrot 9 4 1 11 8 9 0 2 0 11 7 8
Raven 0 2 2 0 0 0 0 1 0 1 0 0

Table 1: Results of the study.

The tape measure is essential in measuring each of the four sites so that it can be 100ft by 100ft. Each site was well-demarcated using a marker. The birds’ book was used in recording the selected species of birds present at each study site. Binoculars were used in identifying the bird species that were off the naked eyesight.

According to Costello, Lunt and Williams (2000, p. 117), it is essential to understand the invasive plant species in order to take precautionary measures that will prevent massive destruction of flora and fauna in the ecosystem. In some situation, the invasive plant species are the major carriers of birds’ disease-causing organisms. The plants cause massive extinction of birds, and death of the susceptible natural plants. The invasive species result in a change of climate that may affect the habitat and the sheltering process of the birds. The invasive plant species have the potential of causing drought or excessive rainfall. The invasive plant species may create a favourable climate for the proliferation and propagation of other invasive (Erskine-Ogden & Rejmánek 2005).

Hygiene (environmental) protocol

Phytophthora connamomi is a common fungus in major parks, and Wattle Park is no exemption in the management of the destructive fungus. Wattle Park maintains all its water sources in order to avoid the growth of Phytophthora connamomi. According to Gooden, French and Turner (2009), waters are the main carrier of P. connamomi. The mould is an invasive species that cause plants to die by infecting the roots and other plant tissues (Yokomizo et al. 2009). Wattle Park examines all the trees in order to prevent the decline of biodiversity that is a major tourist attraction and learning centre.

Birds that rest on certain trees may reduce due to the massive change of the ecosystem after the destruction of favourable trees (Erskine-Ogden & Rejmánek 2005). There was a high likelihood of birds resting on trees than shrubs due to limited infection of trees by P. cinnamomi. The organism destroys forests resulting in migration of bird species and other small mammals that rely on flora for food and shelter.

The major management of P. cinnamomi is through use fungicide that contains phosphate salts. Phosphate boosts the plant’s natural defence. There is no absolute treatment of P. cinnamomi (Yokomizo et al. 2009). The prevention measures of P. cinnamomi are maintenance of drainage, implementation of good hygiene protocol, controlling access, and removal of infected plants from the site (Yokomizo et al. 2009, p. 380).

Alberio and Comparatore (2014) argue that environmental hygiene reduces diseases that affect the flora and fauna in a habitat. The wardens in parks and conserved regions should practice standard hygiene practices so that the endangered species of plants and birds do not get infected prior to propagation. Transportation of trees and birds should be with caution and should not be unintentional. Efficient procedures should be in place to assist in the identification of infected plants and birds. Some of the invasive species are intentional while others are unintentional. Controlled access to the park and close monitoring of people visiting the park is among the efficient methods of preventing the introduction of intentional invasive species (Alberio & Comparatore 2014).

On the other hand, introduction of animals in the park requires a standard protocol in order to ensure their safety and propagation. Certain types of trees develop favourable shelters of birds. In Wattle Park, the trees present in site 1 were the most favourable for Noisy miner birds. Majority of invasive species enters Wattle Park through the use of vehicles, aquarium, canals, visitors, and transportation of animals. Some of the invasive species are harmful to the environment, society, and human being (Gooden, French & Turner 2009).

Occupational Health and Safety protocol

The study also aimed and identification of safe methods of conserving the wildlife. The standard protocol from the government bodies ensured a safe environment for conduction of the study and minimization of pollution in the park. The protocol has sections of handling hazards and risks, and mechanisms of improving the maintenance of the park (Gooden, French & Turner 2009). Some of the hazards and precautionary measures to take are animal bites and scratches.

The wild birds may scratch human beings in the park as they snatch the commodities on the researchers’ hands. Additionally, allergy is common in the park due to the presence of different environmental condition. Some of the allergies are itching, skin swelling, breath shortness, allergic rhinitis, and allergic conjunctivitis. Ethical issues are of concern during the study since accidental injuries are likely to occur during the study (Gooden, French & Turner 2009). There are many bird species in the field and require prior knowledge on the birds to investigate during the study.

The safety precaution protocol of the study allowed the researchers to refer constantly to the taxa of the species for accuracy. Care should be of concern in order to minimize distress and pain on the birds with sounds and sophisticated equipment. The researchers should not interfere with the hygiene of the birds, nutrition, and the composition. Grice (2006) suggests that, researchers should receive guidance on the handling, feeding, and housing of the birds from the trained wardens. The taxa of the birds chosen in the study should suit the area of study in order to answer all the research questions.

The wildlife regulations, especially concerning the birds in the Wattle Park should be well read and understood before commencing the study. Birds should not be transported from their habitat without permission from the Wattle Park administration. The researchers should be aware of the study species, response of birds to disturbance, sensitivity to capture and captive maintenance (Grice 2006). Caution is essential on procedures that are likely to have a lasting effect on the birds’ population. The equipment used in the study involved measuring tape, marker, birds’ book, and binoculars.

Data analysis

According to Costello, Lunt and Williams (2000), continuous variables such as number of birds per tree and per site were compared across the study group using Kruskal-Wallis tests followed by Mann-Whitney paired tests. Chi-square (χ2) test was used for comparing proportions of the number of birds in trees and those in the shrubs. Regression was used in determining the association of the different bird species to the habitat area. The average number of Magpie, crow, rainbow parrot, rosella parrot, noisy miner, species number 1, Green parrot species in site 1, 2,3, and 4 are as shown in the table 2.

Birds Type Trees Site 1 Trees Site 2 Shrubs Site 1 Shrubs Site 2
Magpie 7 2 4 3
Crow 2 8 4 3
Rainbow Parrot 2 1 4 4
Rosella Parrot 2 2 1 2
Noisy miner 15 15 6 12
Species number 1 2 1 1 0
Green Parrot 5 10 1 9
Raven 2 0 1 1

Table 2: Average birds present at the four sites.

The research study aimed at comparing the habitat of birds on trees and shrubs according to Table 3.

Bird Type Trees Shrubs
Magpie 5 4
Crow 5 4
Rainbow Parrot 2 4
Rosella Parrot 2 2
Noisy miner 15 2
Species number 1 2 1
Green Parrot 8 5
Raven 1 1

Table 3: comparison of birds on tree and shrub habitat.

Table 4 gives descriptive statistics of the results of trees and shrubs inhabited by the different bird species. The total number of bird species involved in the study was eight. According to descriptive statistics at least one species of bird was present in the trees and shrubs in the area of study. A maximum of five birds regardless of the species inhabited the shrubs and a maximum of fifteen birds regardless of the species inhabited the trees. On average, three species of birds inhabited the shrubs in the areas of study and five species of birds inhabited the trees in each area of study. The standard deviation values show the expected number of birds on trees and shrubs. The trees have a high dispersion; meaning that more species of birds are likely to inhabit the tees than the shrubs.

Descriptive Statistics

N Minimum Maximum Mean Std. Deviation
SHRUBS 8 1 5 2.88 1.553
TREES 8 1 15 5.00 4.660
Valid N (listwise) 8

Table 4: Descriptive Statistics.

Case processing data shows chi-square tests on bird type of trees. That is the variations of the observed bird species and expected bird species. According to the results, there is a significant difference between the observed and expected bird species of shrubs and trees. The expected minimum count on trees and shrub are thirteen birds. The difference is so high that it gives a significance of 0.275 on Pearson chi-square trees and 0.293 on shrubs. Table 5 gives chi-square tests on birds type versus trees and Table 6 gives chi-square tests on bird type versus shrubs in the area of study. The results of the scatter plot shows no correlation significance between the trees and the shrubs.

Table 5: Chi-Square tests on birds type versus trees.

Chi-Square Tests

Value df Asymp. Sig. (2-sided)
Pearson Chi-Square 32.000(a) 28 .275
Likelihood Ratio 23.907 28 .686
N of Valid Cases 8

a 40 cells (100.0%) have expected count less than 5. The minimum expected count is.13.

Table 6: Chi-Square tests on birds type versus shrubs.

Chi-Square Tests

Value df Asymp. Sig. (2-sided)
Pearson Chi-Square 24.000(a) 21 .293
Likelihood Ratio 21.134 21 .451
N of Valid Cases 8

a 32 cells (100.0%) have expected count less than 5. The minimum expected count is.13.


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