Aphelocoma Californica Research Articles

Competing for seed dispersal: evidence for the role of avian seed hoarders in mediating apparent predation among oaks

Summary In communities of large‐seeded tree species, generalist seed hoarders often link the temporally variable dynamics of various species in ways that can result in indirect ecological interactions. A special case of such interactions is ‘apparent predation’ – when variation in seed production of one tree species changes the outcome of the interaction between seed hoarders and another tree species from seed dispersal mutualism to predation. We investigated how two species of avian hoarders responded to differences in acorn availability among individual valley oaks (Quercus lobata) and across a landscape dominated by blue oaks (Q. douglasii) to determine whether seed dispersal and predation dynamics result in apparent predation between these oak species. California scrub‐jays (Aphelocoma californica), high‐quality seed dispersers with large spatial scales of resource perception, showed strong numerical and functional responses to individually large Q. lobata acorn crops when landscape‐level acorn crops were low, but the numerical response was not observed when Q. douglasii produced a good acorn crop the subsequent year. In contrast, acorn woodpeckers (Melanerpes formicivorus), which are significant acorn predators, exhibited a consistent functional response to individual Q. lobata acorn crops independent of landscape‐wide availability. Consequently, Q. lobata experienced increased predation and a near absence of high‐quality seed dispersal when Q. douglasii acorns were abundant. Our results suggest that apparent predation among oak species can arise from contrasting responses of generalist seed predators and dispersers to acorn availability on different spatial scales. Thus, the spatial scale of resource perception, which can differ greatly among generalist seed hoarders, may provide a proximate mechanism underlying indirect, temporally variable ecological affects such as apparent predation among sympatric species of large‐seeded trees. A lay summary is available for this article.

Western scrub-jays (Aphelocoma californica) solve multiple-string problems by the spatial relation of string and reward.

String-pulling is a widely used paradigm in animal cognition research to assess what animals understand about the functionality of strings as a means to obtain an out-of-reach reward. This study aimed to systematically investigate what rules Western scrub-jays (Aphelocoma californica) use to solve different patterned string tasks, i.e. tasks in which subjects have to choose between two or more strings of which only one is connected to the reward, or where one is more efficient. Arranging strings in a parallel configuration showed that the jays were generally capable of solving multiple-string tasks and acted in a goal-directed manner. The slanted and crossed configurations revealed a reliance on a “proximity rule”, that is, a tendency to choose the string-end closest to the reward. When confronted with strings of different lengths attached to rewards at different distances the birds chose according to the reward distance, preferring the reward closest to them, and were sensitive to the movement of the reward, but did not consistently prefer the shorter and therefore more efficient string. Generally, the scrub-jays were successful in tasks where the reward was closest to the string-ends they needed to pull or when string length and reward distance correlated, but the birds had problems when the wrong string-end was closest to the reward or when the food items were in close proximity to each other. These results show that scrub-jays had a partial understanding of the physical principles underlying string-pulling but relied on simpler strategies such as the proximity rule to solve the tasks.Electronic supplementary materialThe online version of this article (doi:10.1007/s10071-016-1018-x) contains supplementary material, which is available to authorized users.

House Finch (Haemorhous mexicanus) Conjunctivitis, and Mycoplasma spp. Isolated from North American Wild Birds, 1994-2015.

Sampling wild birds for mycoplasma culture has been key to the study of House Finch (Haemorhous mexicanus) conjunctivitis, yielding isolates of Mycoplasma gallisepticum spanning the temporal and geographic ranges of disease from emergence to endemicity. Faced with the challenges and costs of sample collection over time and from remote locations for submission to our laboratory for mycoplasma culture, protocols evolved to achieve a practical optimum. Herein we report making M. gallisepticum isolates from House Finches almost every year since the disease emerged in 1994, and we now have 227 isolates from 17 states. Our wild bird host range for M. gallisepticum isolates includes Blue Jay ( Cyanocitta cristata ), American Goldfinch (Spinus tristis), Lesser Goldfinch (Spinus psaltria), Purple Finch (Haemorhous purpureus), Evening Grosbeak ( Coccothraustes vespertinus ), and herein first reports for Western Scrub-jay ( Aphelocoma californica ), and American Crow ( Corvus brachyrhynchos ). By collecting and identifying isolates from birds with clinical signs similar to those of House Finch conjunctivitis, we also expanded the known host range of Mycoplasma sturni and obtained isolates from additional wild bird species. Accumulating evidence shows that a diverse range of wild bird species may carry or have been exposed to M. gallisepticum in the US, as in Europe and Asia. Therefore, the emergence of a pathogenic M. gallisepticum strain in House Finches may actually be the exception that has allowed us to identify the broader epidemiologic picture.

Counting on your friends: The role of social environment on quantity discrimination

Quantity discrimination has been established in a range of species. However, most demonstrations of quantity discrimination control for social factors by testing animals individually. I tested whether sociality affects quantity discrimination in the wild by comparing the performances of the highly social Mexican jay (MJ; Aphelocoma wollweberi) and the territorial Western scrub jay (WJ; Aphelocoma californica). The birds were given a choice between two lines of peanuts that differed in initial quantity ranging from 2 vs 8 to 14 vs 16. Their choices were recorded until all peanuts were eaten or cached. Whereas non-social WJ selected the larger quantity across all the trials significantly more than chance, social MJ selected the larger line only when the difference in the number of peanuts between lines was small. In MJ, individual choice when selecting the large or small quantity was influenced by what line the previous bird had chosen when the difference in lines was large, with followers significantly more likely to select the smaller quantity. WJ were not significantly affected by the choices of other individuals. The only factors that influenced WJ choice were ratio and total differences between the two quantities. These results suggests that in certain scenarios, both species can discriminate between different quantities. However, MJ were greatly influenced by social factors, a previously untested factor, while WJ were only influenced by ratio and total difference between the quantities, consistent with findings in other species. Overall, this study demonstrates the important role of sociality in numerical cognitive performance, a previously overlooked factor.

The effect of within-year variation in acorn crop size on seed harvesting by avian hoarders.

Spatial and temporal variation in resource distribution affect the movement and foraging behavior of many animals. In the case of animal-dispersed trees, numerous studies have addressed masting-the synchronized variation in seed production between years-but the fitness consequences of spatial variation in seed production within a year are unclear. We investigated the effects of variable acorn production in a population of valley oaks (Quercus lobata) on the composition and behavior of the avian-disperser community. We found that western scrub-jays (Aphelocoma californica), high-quality dispersers that store seeds in the ground, were attracted to, and exhibited increased per capita dispersal rates from, trees with large acorn crops. In contrast, acorn woodpeckers (Melanerpes formicivorus), low-quality dispersers that store acorns in trees where they are unlikely to germinate, increased per capita hoarding rates but did not attend trees with large seed crops in higher numbers, suggesting that the two species responded to resources on different spatial scales. Antagonistic interactions within and between species increased with the number of birds attending a tree, resulting in a potential cost for foraging birds, but did not reduce dispersal rates. Using a simulation model, we estimated that trees with large initial crops experienced a greater proportion (77 %) of high-quality seed dispersal events than trees with small crops (62 %). Our findings provide support for a mechanistic link between seed production and foraging behavior of seed dispersers as predicted by the predator dispersal hypothesis for the functional consequences of variable seed production in hoarder-dispersed trees.

Clark’s nutcrackers (Nucifraga columbiana) are sensitive to distance, but not lighting when caching in the presence of a conspecific

We examined the caching behavior of the Clark’s nutcracker (Nucifraga columbiana), a relatively asocial corvid bird, during social and non-social conditions with conspecifics. Past work by Dally et al., (2004, 2005a) has found that the related but more social scrub jay (Aphelocoma californica) caches food in locations that are far away or that are more dimly illuminated when in the presence of an observer. Here, we used procedures comparable to those of Dally’s group to examine if the less social nutcracker is also sensitive to these same factors when caching in the presence of a conspecific. We found that nutcrackers cached nuts farther away, but showed no preference for caching in a dimly compared to a brightly illuminated area when in the presence of a conspecific observer. When comparing the measures of cache protection used in the past work with scrub jays the results are consistent with the social organization of these birds; that is, the less social nutcracker engaged in fewer cache protection behaviors than the more social scrub jays, However, we explore other possible explanations for our findings given the wider body of literature on corvid cache protection suggesting that nutcrackers and scrub jays may be more comparable.

Sequence capture of ultraconserved elements from bird museum specimens

New DNA sequencing technologies are allowing researchers to explore the genomes of the millions of natural history specimens collected prior to the molecular era. Yet, we know little about how well specific next-generation sequencing (NGS) techniques work with the degraded DNA typically extracted from museum specimens. Here, we use one type of NGS approach, sequence capture of ultraconserved elements (UCEs), to collect data from bird museum specimens as old as 120years. We targeted 5060 UCE loci in 27 western scrub-jays (Aphelocoma californica) representing three evolutionary lineages that could be species, and we collected an average of 3749 UCE loci containing 4460 single nucleotide polymorphisms (SNPs). Despite older specimens producing fewer and shorter loci in general, we collected thousands of markers from even the oldest specimens. More sequencing reads per individual helped to boost the number of UCE loci we recovered from older specimens, but more sequencing was not as successful at increasing the length of loci. We detected contamination in some samples and determined that contamination was more prevalent in older samples that were subject to less sequencing. For the phylogeny generated from concatenated UCE loci, contamination led to incorrect placement of some individuals. In contrast, a species tree constructed from SNPs called within UCE loci correctly placed individuals into three monophyletic groups, perhaps because of the stricter analytical procedures used for SNP calling. This study and other recent studies on the genomics of museum specimens have profound implications for natural history collections, where millions of older specimens should now be considered genomic resources.

Hint-seeking behaviour of western scrub-jays in a metacognition task.

Metacognitive processes during memory retrieval can be tested by examining whether or not animals can assess their knowledge state when they are faced with a memory test. In a typical foraging task, food is hidden in one of the multiple tubes and the subjects are given an opportunity to check the contents of the tubes before choosing the one that they thought contained food. Following the findings from our previous study that western scrub-jays (Aphelocoma californica) can make prospective metacognition judgements, this study tested the scrub-jays' concurrent metacognition judgements. In a series of experiments, uncertainty about the food location was induced in three ways: by making the baiting process visibly unavailable, by inserting a delay between the baiting and food retrieval, and by moving the location of the bait. The jays looked into the tubes more often during the conditions that were consistent with high uncertainty. In addition, their looking behaviour was associated not with the sight of food but with information about the location of the food. These findings suggest that the jays can differentiate the states of knowing and not knowing about certain information and take appropriate action to complement their missing knowledge.

WEST NILE VIRUS-RELATED TRENDS IN AVIAN MORTALITY IN CALIFORNIA, USA, 2003-12.

West Nile virus (WNV) is an arbovirus transmitted enzootically by Culex mosquitoes among avian hosts. Since 2000, the California Dead Bird Surveillance Program (DBSP) has tracked avian mortality reported by the public on a telephone hotline and website and measured the prevalence of WNV infection in dead birds. We summarize herein WNV prevalence in dead birds tested and variation of WNV transmission over time and space with the use of DBSP data from 2003 to 2012. Prevalence among dead birds was highest in 2004, 2008, and 2012. This pattern was similar to peak WNV infection years for mosquitoes but not to human WNV incidence. Although American Crows (Corvus brachyrhynchos) were most frequently reported and tested, this species ranked third in infection prevalence (44%) after Yellow-billed Magpies (Pica nuttalli; 62%) and Western Scrub-Jays (Aphelocoma californica; 48%). Overall prevalence in American Robin (Turdus migratorius), House Finch (Haemorhous mexicanus), and House Sparrow (Passer domesticus) carcasses ranged from 18% to 22%. Corvid WNV prevalence was highest in South Coast, Bay/Delta, Sacramento, and San Joaquin valleys, and Klamath/North Coast bioregions, overlapping areas of elevated WNV activity in other surveillance measurements. Bioregional analysis revealed the avian species most likely to be reported and found positive in each bioregion. Our results may be useful to WNV surveillance and control efforts and provide insight into bird population trends in California.

Occurrence of western scrub-jays (Aphelocoma californica) near forest edges in fragmented golden-cheeked warbler (Setophaga chrysoparia) habitat

The western scrub-jay (Aphelocoma californica) is a common nest predator and has been documented depredating nests of the federally endangered golden-cheeked warbler (Setophaga chrysoparia), a woodland songbird, in central Texas. We conducted opportunistic and transect surveys for western scrub-jays across two vegetation classes (woodland and shrub-scrub) to investigate the proximity of scrub-jays to golden-cheeked warblers breeding in a fragmented landscape. We used a chi-square test to compare the number of observed and expected scrub-jay detections for each vegetation class. To investigate if scrub-jays are an edge-occupying species, we compared the distance to nearest vegetation edge of actual scrub-jay detections to a null distribution of mean random distances. We found that scrub-jays occur in areas closer to vegetation class boundaries but do not appear to prefer one vegetation type over the other. Our findings suggest that golden-cheeked warblers may have higher nest predation risk in fragmented areas of their breeding range.

Speciation in Western Scrub-Jays, Haldane's rule, and genetic clines in secondary contact.

BackgroundHaldane’s Rule, the tendency for the heterogametic sex to show reduced fertility in hybrid crosses, can obscure the signal of gene flow in mtDNA between species where females are heterogametic. Therefore, it is important when studying speciation and species limits in female-heterogametic species like birds to assess the signature of gene flow in the nuclear genome as well. We studied introgression of microsatellites and mtDNA across a secondary contact zone between coastal and interior lineages of Western Scrub-Jays (Aphelocoma californica) to test for a signature of Haldane’s Rule: a narrower cline of introgression in mtDNA compared to nuclear markers.ResultsOur initial phylogeographic analysis revealed that there is only one major area of contact between coastal and interior lineages and identified five genetic clusters with strong spatial structuring: Pacific Slope, Interior US, Edwards Plateau (Texas), Northern Mexico, and Southern Mexico. Consistent with predictions from Haldane’s Rule, mtDNA showed a narrower cline than nuclear markers across a transect through the hybrid zone. This result is not being driven by female-biased dispersal because neutral diffusion analysis, which included estimates of sex-specific dispersal rates, also showed less diffusion of mtDNA. Lineage-specific plumage traits were associated with nuclear genetic profiles for individuals in the hybrid zone, indicating that these differences are under genetic control.ConclusionsThis study adds to a growing list of studies that support predictions of Haldane’s Rule using cline analysis of multiple loci of differing inheritance modes, although alternate hypotheses like selection on different mtDNA types cannot be ruled out. That Haldane’s Rule appears to be operating in this system suggests a measure of reproductive isolation between the Pacific Slope and interior lineages. Based on a variety of evidence from the phenotype, ecology, and genetics, we recommend elevating three lineages to species level: A. californica (Pacific Slope); A. woodhouseii (Interior US plus Edwards Plateau plus Northern Mexico); A. sumichrasti (Southern Mexico). The distinctive Edwards Plateau population in Texas, which was monophyletic in mtDNA except for one individual, should be studied in greater detail given habitat threat.

Crouching towhee, hidden scrub-jay: California towhees,Melozone crissalis,attack conspecific mobbing partners while assaulting a western scrub-jay,Aphelocoma californica

We describe an encounter of eight territorial California towhees (Melozone crissalis), alternately engaged in mobbing a western scrub-jay (Aphelocoma californica) and vigorous conspecific attack and display. We additionally characterize a previously unreported crouching posture adopted by the towhees while surrounding the scrub-jay and hypothesize that this posture communicates submissiveness to conspecific owners of a territory. We suggest that this behavioral sequence resulted from a conflict between cooperation among pairs and defense of resources among pairs, wherein behaviors consistent with both were exhibited nearly simultaneously.

Dead heterospecifics as cues of risk in the environment: Does size affect response?

Organisms can minimize their exposure to risk of death or injury by assessing their environment and modifying their behavior accordingly. There is evidence that the current or recent presence of a predator introduces cues to the environment that organisms may use in risk assessment. However, we know little about whether terrestrial organisms use the remains of victims of predation as one such cue of elevated predation risk. A previous study showed that western scrub-jays (Aphelocoma californica) respond both to dead conspecifics and to encounters with a predator with alarm calling and aggregation (cacophonous aggregations), suggesting that they use dead conspecifics as indirect evidence of predation risk. Here we examine whether western scrub-jays also use dead heterospecifics as an indicator of risk. We find that jays respond with cacophonous aggregations to dead sympatric and allopatric jay-size heterospecifics but react weakly if at all to smaller heterospecifics. This suggests that size may be an important factor in determining whether a dead heterospecific is a relevant cue of risk. To our knowledge this is the first controlled experiment showing an animal using the visual cue provided by a dead heterospecific as an indicator of risk and communicating this risk to other conspecifics.

No evidence of temporal preferences in caching by Western scrub-jays (Aphelocoma californica)

Humans and other animals often favour immediate gratification over long-term gain. Primates, including humans, appear more willing to wait for rewards than other animals, such as rats or pigeons. Another group displaying impressive patience are the corvids, which possess large brains and show sophisticated cognitive abilities. Here, we assess intertemporal choice in one corvid species, the Western scrub-jay (Aphelocoma californica). These birds cache food for future consumption and respond flexibly to future needs. Cache-theft and cache-degradation are time-dependent processes in scrub-jay ecology that might necessitate sensitivity to delays between caching and retrieval. We adopt a caching paradigm with delays of up to 49h. Across two experiments we find no evidence of a preference for earlier recovery. We highlight the possibility that, although scrub-jays can discriminate between the present and the future, they may not understand how far into the future an event will occur.

Western scrub-jays allocate longer observation time to more valuable information

When humans mentally reconstruct past events and imagine future scenarios, their subjective experience of mentally time travelling is accompanied by the awareness of doing so. Despite recent popularity of studying episodic memory in animals, such phenomenological consciousness has been extremely difficult to demonstrate without agreed behavioural markers of consciousness in non-linguistic subjects. We presented western scrub-jays (Aphelocoma californica) with a task requiring them to allocate observing time between two peepholes to see food being hidden in either of two compartments, one where observing the hiding location was necessary to later relocate the food, and another where food could easily be found without watching. Jays first separately experienced these consequences of possessing information in each compartment and subsequently, once given a choice, made more looks and spent more time looking into the compartment where information was necessary than into the compartment where it was unnecessary. Thus, the jays can collect information to solve a future problem. Moreover, they can differentiate sources of information according to their potential value and modify behaviour to efficiently collect important, usable information. This is the first evidence of metacognition in a species that passes the behavioural criteria for both retrospective and prospective mental time travel.

The effects of low levels of light at night upon the endocrine physiology of western scrub‐jays (Aphelocoma californica)

Florida scrub-jays (Aphelocoma coerulescens) in the suburbs breed earlier than jays in native habitat. Amongst the possible factors that influence this advance (e.g., food availability, microclimate, predator regime, etc.), is exposure to artificial lights at night (LAN). LAN could stimulate the reproductive axis of the suburban jays. Alternatively, LAN could inhibit pineal melatonin (MEL), thus removing its inhibitory influence on the reproductive axis. Because Florida scrub-jays are a threatened species, we used western scrub-jays (Aphelocoma californica) to investigate the effects of LAN upon reproductive hormones and melatonin. Jays were held under conditions in which the dark-phase of the light:dark cycle was without illumination and then under low levels of LAN. Under both conditions, birds were exposed first to short-days (9.5L:14.5D) that were gradually increased to long-days (14.5L:9.5D). At various times, blood samples were collected during the light part of the cycle to measure reproductive hormones (luteinizing hormone, LH; testosterone, T; and estradiol, E2 ). Similarly, samples to assess melatonin were collected during the dark. In males, LAN caused a depression in LH levels and levels were ∼4× greater under long- than short-days. In females, there was no effect of LAN or photoperiod upon LH. LAN resulted in depressed T levels in females, although there was no effect on T in males. E2 levels in both sexes were lower under LAN than under an unlighted dark-phase. Paradoxically, MEL was higher in jays under LAN, and under long-days. MEL did not differ by sex. LAN disrupted the extraordinarily strong correlation between T and E2 that existed under unlighted nocturnal conditions. Overall, our findings fail to support the hypothesis that LAN stimulates the reproductive axis. Rather, the data demonstrate that LAN tends to inhibit reproductive hormone secretion, although not in a consistent fashion between the sexes.

Re-caching by Western Scrub-Jays (Aphelocoma californica) Cannot Be Attributed to Stress

Western scrub-jays (Aphelocoma californica) live double lives, storing food for the future while raiding the stores of other birds. One tactic scrub-jays employ to protect stores is “re-caching”—relocating caches out of sight of would-be thieves. Recent computational modelling work suggests that re-caching might be mediated not by complex cognition, but by a combination of memory failure and stress. The “Stress Model” asserts that re-caching is a manifestation of a general drive to cache, rather than a desire to protect existing stores. Here, we present evidence strongly contradicting the central assumption of these models: that stress drives caching, irrespective of social context. In Experiment (i), we replicate the finding that scrub-jays preferentially relocate food they were watched hiding. In Experiment (ii) we find no evidence that stress increases caching. In light of our results, we argue that the Stress Model cannot account for scrub-jay re-caching.

Eurasian jays, Garrulus glandarius, flexibly switch caching and pilfering tactics in response to social context

Corvids such as jays and ravens cache food for future consumption and can remember the location of caches that they have seen others make. Given the risk of caches being pilfered by observers, corvids limit opportunities for conspecifics to witness caching events. Faced with cache protection tactics, pilferers should also utilize tactics to maximize their success. Cacher–pilferer interactions and their underlying cognition have largely been investigated in semisocial ravens, Corvus corax, and western scrub-jays, Aphelocoma californica. However to understand the factors influencing the development of these abilities, data are required from species that differ in their socioecology from ravens and western scrub-jays. In the current study, we tested the caching and pilfering behaviour of territorial Eurasian jays in two social contexts. In one context, subjects competed with a dominant conspecific, while in the other the same individuals interacted with a subordinate competitor. When subordinate, birds initially suppressed caching, before caching more in less exposed locations. In contrast, when socially dominant, birds cached more and moved items multiple times. As subordinate pilferers, birds took longer to approach cache sites and approached when the cacher was at a distance, while when dominant, birds rapidly approached the conspecifics’ cache sites, frequently when the cacher was still in the process of caching. Individual jays therefore flexibly switched caching and pilfering tactics in response to the relative dominance of their competitor. We discuss the implications of our results for competing theories on the origin of behavioural flexibility and its underlying complex cognition in the corvid lineage.

Western scrub-jay funerals: cacophonous aggregations in response to dead conspecifics

All organisms must contend with the risk of injury or death; many animals reduce this danger by assessing environmental cues to avoid areas of elevated risk. However, little is known about how organisms respond to one of the most salient visual cues of risk: a dead conspecific. Here we show that the sight of a dead conspecific is sufficient to induce alarm calling and subsequent risk-reducing behavioural modification in western scrub-jays, Aphelocoma californica, and is similar to the response to a predator (a great horned owl, Bubo virginianus, model). Discovery of a dead conspecific elicits vocalizations that are effective at attracting conspecifics, which then also vocalize, thereby resulting in a cacophonous aggregation. Presentations of prostrate dead conspecifics and predator mounts elicited aggregations and hundreds of long-range communication vocalizations, while novel objects did not. In contrast to presentations of prostrate dead conspecifics, presentations of a jay skin mounted in an upright, life-like pose elicited aggressive responses, suggesting the mounted scrub-jay was perceived to be alive and the prostrate jay was not. There was a decrease of foraging in the area during presentations of prostrate dead conspecifics and predator mounts, which was still detectable 24 h later. Foraging returned to baseline levels 48 h after presentations. Novel objects and mounted jays did not affect foraging. Our results show that without witnessing the struggle and manner of death, the sight of a dead conspecific is used as public information and that this information is actively shared with conspecifics and used to reduce exposure to risk.

Nuevos avistamientos de aves para Tamaulipas, México

Los inventarios y registros avifaunísticos facilitan el conocimiento de la composición de las comunidades de aves y ayudan a la comprensión de las interacciones en los ecosistemas. En este trabajo obtuvimos registros notables de cinco especies de aves de 2005 a 2011 en los municipios de Altamira, El Mante, González, Jaumave, Madero, Matamoros, Miquihuana y Soto La Marina, en el estado de Tamaulipas. Registramos por primera vez la presencia de Aphelocoma californica e Icterus wagleri en el estado, confirmando las predicciones de algunos autores. Con la colecta de un nido, reafirmamos la presencia de Psarocolius montezuma en el sur del estado. Registramos nuevamente la presencia de Falco femoralis en la entidad, especie reportada hace algunos años como extirpada. ParaLepidocolaptes affinis definimos parte de su área de distribución en los límites neotropicales del estado. Las modificaciones antropogénicas en los ecosistemas son algunos de los principales factores que influyen en los movimientos distribucionales de las especies; por esto, es necesario incrementar el esfuerzo de muestreo que permita el registro de un mayor número de especies y así poder tener un mejor conocimiento de su distribución y temporalidad a nivel local y regional para entender su historia natural y ecología a escalas más finas.